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  • richardmitnick 4:11 pm on May 13, 2021 Permalink | Reply
    Tags: "World’s fastest information-fuelled engine designed by SFU researchers", , Engines of this type were first proposed over 150 years ago but actually making them has only recently become possible., Laser Technology, , , This engine converts the random jiggling of a microscopic particle into stored energy.   

    From Simon Fraser University (CA): “World’s fastest information-fuelled engine designed by SFU researchers” 

    From Simon Fraser University (CA)

    May 11, 2021

    Simon Fraser University researchers have designed a remarkably fast engine that taps into a new kind of fuel — information.

    1
    PhD student Tushar Saha working on the information ratchet, an experimental apparatus that lifts a heavy microscopic particle using information.

    The development of this engine which converts the random jiggling of a microscopic particle into stored energy, is outlined in research published this week in the PNAS and could lead to significant advances in the speed and cost of computers and bio-nanotechnologies.

    SFU physics professor and senior author John Bechhoefer says researchers’ understanding of how to rapidly and efficiently convert information into “work” may inform the design and creation of real-world information engines.



    “We wanted to find out how fast an information engine can go and how much energy it can extract, so we made one,” says Bechhoefer, whose experimental group collaborated with theorists led by SFU physics professor David Sivak.

    Engines of this type were first proposed over 150 years ago but actually making them has only recently become possible.

    “By systematically studying this engine, and choosing the right system characteristics, we have pushed its capabilities over ten times farther than other similar implementations, thus making it the current best-in-class,” says Sivak.

    The information engine designed by SFU researchers consists of a microscopic particle immersed in water and attached to a spring which, itself, is fixed to a movable stage. Researchers then observe the particle bouncing up and down due to thermal motion.

    “When we see an upward bounce, we move the stage up in response,” explains lead author and PhD student Tushar Saha. “When we see a downward bounce, we wait. This ends up lifting the entire system using only information about the particle’s position.”

    Repeating this procedure, they raise the particle “a great height, and thus store a significant amount of gravitational energy,” without having to directly pull on the particle.

    Saha further explains that, “in the lab, we implement this engine with an instrument known as an optical trap, which uses a laser to create a force on the particle that mimics that of the spring and stage.”



    Joseph Lucero, a Master of Science student adds, “in our theoretical analysis, we find an interesting trade-off between the particle mass and the average time for the particle to bounce up. While heavier particles can store more gravitational energy, they generally also take longer to move up.”



    “Guided by this insight, we picked the particle mass and other engine properties to maximize how fast the engine extracts energy, outperforming previous designs and achieving power comparable to molecular machinery in living cells, and speeds comparable to fast-swimming bacteria,” says postdoctoral fellow Jannik Ehrich.

    See the full article here.

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    Simon Fraser University (CA) is a public research university in British Columbia, Canada, with three campuses: Burnaby (main campus), Surrey, and Vancouver. The 170-hectare (420-acre) main Burnaby campus on Burnaby Mountain, located 20 kilometres (12 mi) from downtown Vancouver, was established in 1965 and comprises more than 30,000 students and 160,000 alumni. The university was created in an effort to expand higher education across Canada.

    Simon Fraser University (CA) is a member of multiple national and international higher education, including the Association of Commonwealth Universities, International Association of Universities, and Universities Canada (CA). Simon Fraser University has also partnered with other universities and agencies to operate joint research facilities such as the TRIUMF- Canada’s particle accelerator centre [Centre canadien d’accélération des particules] (CA) for particle and nuclear physics, which houses the world’s largest cyclotron, and Bamfield Marine Station, a major centre for teaching and research in marine biology.

    Undergraduate and graduate programs at Simon Fraser University (CA) operate on a year-round, three-semester schedule. Consistently ranked as Canada’s top comprehensive university and named to the Times Higher Education list of 100 world universities under 50, Simon Fraser University (CA)is also the first Canadian member of the National Collegiate Athletic Association, the world’s largest college sports association. In 2015, Simon Fraser University (CA) became the second Canadian university to receive accreditation from the Northwest Commission on Colleges and Universities. Simon Fraser University (CA) faculty and alumni have won 43 fellowships to the Royal Society of Canada [Société royale du Canada](CA), three Rhodes Scholarships and one Pulitzer Prize. Among the list of alumni includes two former premiers of British Columbia, Gordon Campbell and Ujjal Dosanjh, owner of the Vancouver Canucks NHL team, Francesco Aquilini, Prime Minister of Lesotho, Pakalitha Mosisili, director at the Max Planck Society [Max Planck Gesellschaft](DE) , Robert Turner, and humanitarian and cancer research activist, Terry Fox.

     
  • richardmitnick 9:55 pm on May 12, 2021 Permalink | Reply
    Tags: "Laser Communications- Empowering More Data Than Ever Before", Laser Technology,   

    From NASA Goddard Space Flight Center: “Laser Communications- Empowering More Data Than Ever Before” 

    NASA Goddard Banner

    From NASA Goddard Space Flight Center

    May 12, 2021

    Katherine Schauer
    katherine.s.schauer@nasa.gov
    NASA’s Goddard Space Flight Center, Greenbelt, Md.

    1
    Illustration of the U.S. Department of Defense’s Space Test Program Satellite-6 (STPSat-6) with the Laser Communications Relay Demonstration (LCRD) payload communicating data over infrared links. Credit: NASA.

    Launching this summer, NASA’s Laser Communications Relay Demonstration (LCRD) will showcase the dynamic powers of laser communications technologies. With NASA’s ever-increasing human and robotic presence in space, missions can benefit from a new way of “talking” with Earth.

    Since the beginning of spaceflight in the 1950s, NASA missions have leveraged radio frequency communications to send data to and from space. Laser communications, also known as optical communications, will further empower missions with unprecedented data capabilities.

    1
    Graphic representation of the difference in data rates between radio and laser communications. Credit: NASA.

    Why Lasers?

    As science instruments evolve to capture high-definition data like 4K video, missions will need expedited ways to transmit information to Earth. With laser communications, NASA can significantly accelerate the data transfer process and empower more discoveries.

    Laser communications will enable 10 to 100 times more data transmitted back to Earth than current radio frequency systems. It would take roughly nine weeks to transmit a complete map of Mars back to Earth with current radio frequency systems. With lasers, it would take about nine days.

    Additionally, laser communications systems are ideal for missions because they need less volume, weight, and power. Less mass means more room for science instruments, and less power means less of a drain of spacecraft power systems. These are all critically important considerations for NASA when designing and developing mission concepts.

    “LCRD will demonstrate all of the advantages of using laser systems and allow us to learn how to use them best operationally,” said Principal Investigator David Israel at NASA’s Goddard Space Flight Center in Greenbelt, Maryland. “With this capability further proven, we can start to implement laser communications on more missions, making it a standardized way to send and receive data.”

    How it Works

    Both radio waves and infrared light are electromagnetic radiation with wavelengths at different points on the electromagnetic spectrum. Like radio waves, infrared light is invisible to the human eye, but we encounter it every day with things like television remotes and heat lamps.

    Missions modulate their data onto the electromagnetic signals to traverse the distances between spacecraft and ground stations on Earth. As the communication travels, the waves spread out.

    The infrared light used for laser communications differs from radio waves because the infrared light packs the data into significantly tighter waves, meaning ground stations can receive more data at once. While laser communications aren’t necessarily faster, more data can be transmitted in one downlink.

    Laser communications terminals in space use narrower beam widths than radio frequency systems, providing smaller “footprints” that can minimize interference or improve security by drastically reducing the geographic area where someone could intercept a communications link. However, a laser communications telescope pointing to a ground station must be exact when broadcasting from thousands or millions of miles away. A deviation of even a fraction of a degree can result in the laser missing its target entirely. Like a quarterback throwing a football to a receiver, the quarterback needs to know where to send the football, i.e. the signal, so that the receiver can catch the ball in stride. NASA’s laser communications engineers have intricately designed laser missions to ensure this connection can happen.

    Laser Communications Relay Demonstration

    Located in geosynchronous orbit, about 22,000 miles above Earth, LCRD will be able to support missions in the near-Earth region. LCRD will spend its first two years testing laser communications capabilities with numerous experiments to refine laser technologies further, increasing our knowledge about potential future applications.

    LCRD’s initial experiment phase will leverage the mission’s ground stations in California and Hawaii, Optical Ground Station 1 and 2, as simulated users. This will allow NASA to evaluate atmospheric disturbances on lasers and practice switching support from one user to the next. After the experiment phase, LCRD will transition to supporting space missions, sending and receiving data to and from satellites over infrared lasers to demonstrate the benefits of a laser communications relay system.

    The first in-space user of LCRD will be NASA’s Integrated LCRD Low-Earth Orbit User Modem and Amplifier Terminal (ILLUMA-T), which is set to launch to the International Space Station in 2022. The terminal will receive high-quality science data from experiments and instruments onboard the space station and then transfer this data to LCRD at 1.2 gigabits per second. LCRD will then transmit it to ground stations at the same rate.

    LCRD and ILLUMA-T follow the groundbreaking 2013 Lunar Laser Communications Demonstration, which downlinked data over a laser signal at 622 megabits-per-second, proving the capabilities of laser systems at the Moon. NASA has many other laser communications missions currently in different stages of development. Each of these missions will increase our knowledge about the benefits and challenges of laser communications and further standardize the technology.

    LCRD is slated to launch as a payload on a Department of Defense spacecraft on June 23, 2021.

    LCRD is a NASA payload aboard the Department of Defense’s Space Test Program Satellite-6 (STPSat-6). STPSat-6, part of the third Space Test Program (STP-3) mission, will launch on a United Launch Alliance Atlas V 551 rocket from the Cape Canaveral Space Force Station in Florida. STP is operated by the United States Space Force’s Space and Missile Systems Center.

    LCRD is led by Goddard and in partnership with NASA’s Jet Propulsion Laboratory in Southern California and the MIT (US) Lincoln Laboratory. LCRD is funded through NASA’s Technology Demonstration Missions program, part of the Space Technology Mission Directorate, and the Space Communications and Navigation (SCaN) program, within the Human Exploration and Operations Mission Directorate.

    See the full article here.


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    NASA/Goddard Campus

    NASA’s Goddard Space Flight Center, Greenbelt, MD (US) is home to the nation’s largest organization of combined scientists, engineers and technologists that build spacecraft, instruments and new technology to study the Earth, the sun, our solar system, and the universe.

    Named for American rocketry pioneer Dr. Robert H. Goddard, the center was established in 1959 as NASA’s first space flight complex. Goddard and its several facilities are critical in carrying out NASA’s missions of space exploration and scientific discovery.

    GSFC also operates two spaceflight tracking and data acquisition networks (the NASA Deep Space Network(US) and the Near Earth Network); develops and maintains advanced space and Earth science data information systems, and develops satellite systems for the National Oceanic and Atmospheric Administration(US) .

    GSFC manages operations for many NASA and international missions including the NASA/ESA Hubble Space Telescope; the Explorers Program; the Discovery Program; the Earth Observing System; INTEGRAL; MAVEN; OSIRIS-REx; the Solar and Heliospheric Observatory ; the Solar Dynamics Observatory; Tracking and Data Relay Satellite System ; Fermi; and Swift. Past missions managed by GSFC include the Rossi X-ray Timing Explorer (RXTE), Compton Gamma Ray Observatory, SMM, COBE, IUE, and ROSAT. Typically, unmanned Earth observation missions and observatories in Earth orbit are managed by GSFC, while unmanned planetary missions are managed by the Jet Propulsion Laboratory (JPL) in Pasadena, California(US).

    Goddard is one of four centers built by NASA since its founding on July 29, 1958. It is NASA’s first, and oldest, space center. Its original charter was to perform five major functions on behalf of NASA: technology development and fabrication; planning; scientific research; technical operations; and project management. The center is organized into several directorates, each charged with one of these key functions.

    Until May 1, 1959, NASA’s presence in Greenbelt, MD was known as the Beltsville Space Center. It was then renamed the Goddard Space Flight Center (GSFC), after Robert H. Goddard. Its first 157 employees transferred from the United States Navy’s Project Vanguard missile program, but continued their work at the Naval Research Laboratory in Washington, D.C., while the center was under construction.

    Goddard Space Flight Center contributed to Project Mercury, America’s first manned space flight program. The Center assumed a lead role for the project in its early days and managed the first 250 employees involved in the effort, who were stationed at Langley Research Center in Hampton, Virginia. However, the size and scope of Project Mercury soon prompted NASA to build a new Manned Spacecraft Center, now the Johnson Space Center, in Houston, Texas. Project Mercury’s personnel and activities were transferred there in 1961.

    The Goddard network tracked many early manned and unmanned spacecraft.

    Goddard Space Flight Center remained involved in the manned space flight program, providing computer support and radar tracking of flights through a worldwide network of ground stations called the Spacecraft Tracking and Data Acquisition Network (STDN). However, the Center focused primarily on designing unmanned satellites and spacecraft for scientific research missions. Goddard pioneered several fields of spacecraft development, including modular spacecraft design, which reduced costs and made it possible to repair satellites in orbit. Goddard’s Solar Max satellite, launched in 1980, was repaired by astronauts on the Space Shuttle Challenger in 1984. The Hubble Space Telescope, launched in 1990, remains in service and continues to grow in capability thanks to its modular design and multiple servicing missions by the Space Shuttle.

    Today, the center remains involved in each of NASA’s key programs. Goddard has developed more instruments for planetary exploration than any other organization, among them scientific instruments sent to every planet in the Solar System. The center’s contribution to the Earth Science Enterprise includes several spacecraft in the Earth Observing System fleet as well as EOSDIS, a science data collection, processing, and distribution system. For the manned space flight program, Goddard develops tools for use by astronauts during extra-vehicular activity, and operates the Lunar Reconnaissance Orbiter, a spacecraft designed to study the Moon in preparation for future manned exploration.

     
  • richardmitnick 7:33 am on May 12, 2021 Permalink | Reply
    Tags: , Laser Technology, , , , "Light meets superconducting circuits", Microwave superconducting circuit platforms, Using light to read out superconducting circuits thus overcoming the scaling challenges of quantum systems., HEMTs-low noise high electron mobility transistors, Replacing HEMT amplifiers and coaxial cables with a lithium niobate electro-optical phase modulator and optical fibers respectively., Optical fibers are about 100 times better heat isolators than coaxial cables and are 100 times more compact., Enabling the engineering of large-scale quantum systems without requiring enormous cryogenic cooling power.   

    From Swiss Federal Institute of Technology in Lausanne [EPFL-École Polytechnique Fédérale de Lausanne](CH): “Light meets superconducting circuits” 

    From Swiss Federal Institute of Technology in Lausanne [EPFL-École Polytechnique Fédérale de Lausanne](CH)

    5.12.21
    Amir Youssefi
    Nik Papageorgiou

    EPFL researchers have developed a light-based approach to read out superconducting circuits, overcoming the scaling-up limitations of quantum computing systems.

    1
    No image caption or credit.

    In the last few years, several technology companies including Google, Microsoft, and IBM, have massively invested in quantum computing systems based on microwave superconducting circuit platforms in an effort to scale them up from small research-oriented systems to commercialized computing platforms. But fulfilling the potential of quantum computers requires a significant increase in the number of qubits, the building blocks of quantum computers, which can store and manipulate quantum information.

    But quantum signals can be contaminated by thermal noise generated by the movement of electrons. To prevent this, superconducting quantum systems must operate at ultra-low temperatures – less than 20 milli-Kelvin – which can be achieved with cryogenic helium-dilution refrigerators.

    The output microwave signals from such systems are amplified by low-noise high-electron mobility transistors (HEMTs) at low temperatures. Signals are then routed outside the refrigerator by microwave coaxial cables, which are the easiest solutions to control and read superconducting devices but are poor heat isolators, and take up a lot of space; this becomes a problem when we need to scale up qubits in the thousands.

    Researchers in the group of Professor Tobias J. Kippenberg at EPFL’s School of Basic Sciences have now developed a novel approach that uses light to read out superconducting circuits thus overcoming the scaling challenges of quantum systems. The work is published in Nature Electronics.

    The scientists replaced HEMT amplifiers and coaxial cables with a lithium niobate electro-optical phase modulator and optical fibers respectively. Microwave signals from superconducting circuits modulate a laser carrier and encode information on the output light at cryogenic temperatures. Optical fibers are about 100 times better heat isolators than coaxial cables and are 100 times more compact. This enables the engineering of large-scale quantum systems without requiring enormous cryogenic cooling power. In addition, the direct conversion of microwave signals to the optical domain facilitates long-range transfer and networking between quantum systems.

    “We demonstrate a proof-of-principle experiment using a novel optical readout protocol to optically measure a superconducting device at cryogenic temperatures,” says Amir Youssefi, a PhD student working on the project. “It opens up a new avenue to scale future quantum systems.” To verify this approach, the team performed conventional coherent and incoherent spectroscopic measurements on a superconducting electromechanical circuit, which showed perfect agreement between optical and traditional HEMT measurements.

    Although this project used a commercial electro-optical phase modulator, the researchers are currently developing advanced electro-optical devices based on integrated lithium niobate technology to significantly enhance their method’s conversion efficiency and lower noise.

    Funding: Horizon 2020; Swiss National Science Foundation [Schweizerischer Nationalfonds zur Förderung der wissenschaftlichen Forschung] [Fonds national suisse de la recherche scientifique] (CH) (NCCR-QSIT and Sinergia)

    See the full article here .

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    EPFL bloc

    The Swiss Federal Institute of Technology in Lausanne [EPFL-École polytechnique fédérale de Lausanne](CH) is a research institute and university in Lausanne, Switzerland, that specializes in natural sciences and engineering. It is one of the two Swiss Federal Institutes of Technology, and it has three main missions: education, research and technology transfer.

    The QS World University Rankings ranks EPFL(CH) 14th in the world across all fields in their 2020/2021 ranking, whereas Times Higher Education World University Rankings ranks EPFL(CH) as the world’s 19th best school for Engineering and Technology in 2020.

    EPFL(CH) is located in the French-speaking part of Switzerland; the sister institution in the German-speaking part of Switzerland is the Swiss Federal Institute of Technology ETH Zürich [Eidgenössische Technische Hochschule Zürich)](CH). Associated with several specialized research institutes, the two universities form the Swiss Federal Institutes of Technology Domain (ETH(CH) Domain) which is directly dependent on the Federal Department of Economic Affairs, Education and Research. In connection with research and teaching activities, EPFL(CH) operates a nuclear reactor CROCUS; a Tokamak Fusion reactor; a Blue Gene/Q Supercomputer; and P3 bio-hazard facilities.

    The roots of modern-day EPFL(CH) can be traced back to the foundation of a private school under the name École spéciale de Lausanne in 1853 at the initiative of Lois Rivier, a graduate of the École Centrale Paris (FR) and John Gay the then professor and rector of the Académie de Lausanne. At its inception it had only 11 students and the offices was located at Rue du Valentin in Lausanne. In 1869, it became the technical department of the public Académie de Lausanne. When the Académie was reorganised and acquired the status of a university in 1890, the technical faculty changed its name to École d’ingénieurs de l’Université de Lausanne. In 1946, it was renamed the École polytechnique de l’Université de Lausanne (EPUL). In 1969, the EPUL was separated from the rest of the University of Lausanne and became a federal institute under its current name. EPFL(CH), like ETH Zürich(CH), is thus directly controlled by the Swiss federal government. In contrast, all other universities in Switzerland are controlled by their respective cantonal governments. Following the nomination of Patrick Aebischer as president in 2000, EPFL(CH) has started to develop into the field of life sciences. It absorbed the Swiss Institute for Experimental Cancer Research (ISREC) in 2008.

    In 1946, there were 360 students. In 1969, EPFL(CH) had 1,400 students and 55 professors. In the past two decades the university has grown rapidly and as of 2012 roughly 14,000 people study or work on campus, about 9,300 of these being Bachelor, Master or PhD students. The environment at modern day EPFL(CH) is highly international with the school attracting students and researchers from all over the world. More than 125 countries are represented on the campus and the university has two official languages, French and English.

    Organization

    EPFL is organised into eight schools, themselves formed of institutes that group research units (laboratories or chairs) around common themes:

    School of Basic Sciences (SB, Jan S. Hesthaven)

    Institute of Mathematics (MATH, Victor Panaretos)
    Institute of Chemical Sciences and Engineering (ISIC, Emsley Lyndon)
    Institute of Physics (IPHYS, Harald Brune)
    European Centre of Atomic and Molecular Computations (CECAM, Ignacio Pagonabarraga Mora)
    Bernoulli Center (CIB, Nicolas Monod)
    Biomedical Imaging Research Center (CIBM, Rolf Gruetter)
    Interdisciplinary Center for Electron Microscopy (CIME, Cécile Hébert)
    Max Planck-EPFL Centre for Molecular Nanosciences and Technology (CMNT, Thomas Rizzo)
    Swiss Plasma Center (SPC, Ambrogio Fasoli)
    Laboratory of Astrophysics (LASTRO, Jean-Paul Kneib)

    School of Engineering (STI, Ali Sayed)

    Institute of Electrical Engineering (IEL, Giovanni De Micheli)
    Institute of Mechanical Engineering (IGM, Thomas Gmür)
    Institute of Materials (IMX, Michaud Véronique)
    Institute of Microengineering (IMT, Olivier Martin)
    Institute of Bioengineering (IBI, Matthias Lütolf)

    School of Architecture, Civil and Environmental Engineering (ENAC, Claudia R. Binder)

    Institute of Architecture (IA, Luca Ortelli)
    Civil Engineering Institute (IIC, Eugen Brühwiler)
    Institute of Urban and Regional Sciences (INTER, Philippe Thalmann)
    Environmental Engineering Institute (IIE, David Andrew Barry)

    School of Computer and Communication Sciences (IC, James Larus)

    Algorithms & Theoretical Computer Science
    Artificial Intelligence & Machine Learning
    Computational Biology
    Computer Architecture & Integrated Systems
    Data Management & Information Retrieval
    Graphics & Vision
    Human-Computer Interaction
    Information & Communication Theory
    Networking
    Programming Languages & Formal Methods
    Security & Cryptography
    Signal & Image Processing
    Systems

    School of Life Sciences (SV, Gisou van der Goot)

    Bachelor-Master Teaching Section in Life Sciences and Technologies (SSV)
    Brain Mind Institute (BMI, Carmen Sandi)
    Institute of Bioengineering (IBI, Melody Swartz)
    Swiss Institute for Experimental Cancer Research (ISREC, Douglas Hanahan)
    Global Health Institute (GHI, Bruno Lemaitre)
    Ten Technology Platforms & Core Facilities (PTECH)
    Center for Phenogenomics (CPG)
    NCCR Synaptic Bases of Mental Diseases (NCCR-SYNAPSY)

    College of Management of Technology (CDM)

    Swiss Finance Institute at EPFL (CDM-SFI, Damir Filipovic)
    Section of Management of Technology and Entrepreneurship (CDM-PMTE, Daniel Kuhn)
    Institute of Technology and Public Policy (CDM-ITPP, Matthias Finger)
    Institute of Management of Technology and Entrepreneurship (CDM-MTEI, Ralf Seifert)
    Section of Financial Engineering (CDM-IF, Julien Hugonnier)

    College of Humanities (CDH, Thomas David)

    Human and social sciences teaching program (CDH-SHS, Thomas David)

    EPFL Middle East (EME, Dr. Franco Vigliotti)[62]

    Section of Energy Management and Sustainability (MES, Prof. Maher Kayal)

    In addition to the eight schools there are seven closely related institutions

    Swiss Cancer Centre
    Center for Biomedical Imaging (CIBM)
    Centre for Advanced Modelling Science (CADMOS)
    École cantonale d’art de Lausanne (ECAL)
    Campus Biotech
    Wyss Center for Bio- and Neuro-engineering
    Swiss National Supercomputing Centre

     
  • richardmitnick 5:01 pm on May 10, 2021 Permalink | Reply
    Tags: , Laser Technology, , , , "JQI Researchers Generate Tunable Twin Particles of Light", A new technique sees two distinct particles of light enter a chip and two identical twin particles of light leave it., Identical twins might seem “indistinguishable” but in the quantum world the word takes on a new level of meaning., Quantum interference— needed for quantum computers., Inside a resonator a photon from each of the beams spontaneously combine. The researchers then observed how the photons reformed into two indistinguishable photons., The resulting combination of being indistinguishable and entangled is essential for many potential uses of photons in quantum technologies.   

    From Joint Quantum Institute (US): “JQI Researchers Generate Tunable Twin Particles of Light” 

    JQI bloc

    At


    University of Maryland (US)

    May 10, 2021

    Story by Bailey Bedford

    Mohammad Hafezi
    hafezi@umd.edu

    1
    A new technique sees two distinct particles of light enter a chip and two identical twin particles of light leave it. The image artistically combines the journey of twin particles of light along the outer edge of a checkerboard of rings with the abstract shape of its topological underpinnings. Credit: Kaveh Haerian.

    Identical twins might seem “indistinguishable” but in the quantum world the word takes on a new level of meaning. While identical twins share many traits, the universe treats two indistinguishable quantum particles as intrinsically interchangeable. This opens the door for indistinguishable particles to interact in unique ways—such as in quantum interference—that are needed for quantum computers.

    While generating a crowd of photons—particles of light—is as easy as flipping a light switch, it’s trickier to make a pair of indistinguishable photons. And it takes yet more work to endow that pair with a quantum mechanical link known as entanglement. In a paper published May 10, 2021 in the journal Nature Photonics, JQI researchers and their colleagues describe a new way to make entangled twin particles of light and to tune their properties using a method conveniently housed on a chip, a potential boon for quantum technologies that require a reliable source of well-tailored photon pairs.

    The researchers, led by JQI fellow Mohammad Hafezi, designed the method to harness the advantages of topological physics. Topological physics explores previously untapped physical phenomena using the mathematical field of topology, which describes common traits shared by different shapes. (Where geometry concerns angles and sizes, topology is more about holes and punctures—all-encompassing characteristics that don’t depend on local details.) Researchers have made several major discoveries by applying this approach, which describes how quantum particles—like electrons or, in this case, photons—can move in a particular material or device by analyzing its broad characteristics through the lens of topological features that correspond to abstract shapes (such as the donut in the image above). The topological phenomena that have been revealed are directly tied to the general nature of the material; they must exist even in the presence of material impurities that would upset the smooth movement of photons or electrons in most other circumstances.

    Their new method builds on previous work, including the generation of a series of distinguishable photon pairs. In both the new and old experiments, the team created a checkerboard of rings on a silicon chip. Each ring is a resonator that acts like a tiny race track designed to keep certain photons traveling round and round for a long time. But since individual photons in a resonator live by quantum rules, the racecars (photons) can sometimes just pass unchanged through an intervening wall and proceed to speed along a neighboring track.

    The repeating grid of rings mimics the repeating grid of atoms that electrons travel through in a solid, allowing the researchers to design situations for light that mirror well known topological effects in electronics. By creating and exploring different topological environments, the team has developed new ways to manipulate photons.

    “It’s exactly the same mathematics that applies to electrons and photons,” says Sunil Mittal, a JQI postdoctoral researcher and the first author of the paper. “So you get more or less all the same topological features. All the mathematics that you do with electrons, you can simply carry to photonic systems.”

    In the current work, they recreated an electronic phenomenon called the anomalous quantum Hall effect that opens up paths for electrons on the edge of a material. These edge paths, which are called topological edge states, exist because of topological effects, and they can reliably transport electrons while leaving routes through the interior easily disrupted and impassable. Achieving this particular topological effect requires that localized magnetic fields push on electrons and that the total magnetic field when averaged over larger sections of the material cancels out to zero.

    But photons lack the electrical charge that makes electrons susceptible to magnetic shoves, so the team had to recreate the magnetic push in some other way. To achieve this, they laid out the tracks so that it is easier for the photons to quantum mechanically jump between rings in certain directions. This simulates the missing magnetic influence and creates an environment with a photonic version of the anomalous quantum Hall effect and its stable edge paths.

    For this experiment, the team sent two laser beams of two different colors (frequencies) of light into this carefully designed environment. Inside a resonator a photon from each of the beams spontaneously combine. The researchers then observed how the photons reformed into two indistinguishable photons, travelled through the topological edge paths and were eventually ejected from the chip.

    Since the new photons formed inside a resonator ring, they took on the traits (polarization and spatial mode) of the photons that the resonators are designed to hold. The only trait left that the team needed to worry about was their frequencies.

    The researchers matched the frequencies of the photons by selecting the appropriate input frequencies for the two lasers based on how they would combine inside the silicon resonators. With the appropriate theoretical understanding of the experiment, they can produce photons that are quantum mechanically indistinguishable.

    The nature of the formation of the new photons provides the desired quantum characteristics. The photons are quantum mechanically entangled due to the way they were generated as pairs; their combined properties—like the total energy of the pair—are constrained by what the original photons brought into the mix, so observing the property of one instantly reveals the equivalent fact about the other. Until they are observed—that is, detected by the researchers—they don’t exist as two individual particles with distinct quantum states for their frequencies. Rather, they are identical mixtures of possible frequency states called a superposition. The two photons being indistinguishable means they can quantum mechanically interfere with each other

    The resulting combination of being indistinguishable and entangled is essential for many potential uses of photons in quantum technologies. An additional lucky side effect of the researcher’s topological approach is that it gives them a greater ability to adjust the frequencies of the twin photons based on the frequencies they pump into the chip and how well the frequencies match with the topological states on the edge of the device.

    “This is not the only way to generate entangled photon pairs—there are many other devices—but they are not tunable,” Mittal says. “So once you fabricate your device, it is what it is. If you want to change the bandwidth of the photons or do something else, it’s not possible. But in our case, we don’t have to design a new device. We showed that, just by tuning the pump frequencies, we could tune the interference properties. So, that was very exciting.”

    The combination of the devices being tunable and robust against manufacturing imperfections make them an appealing option for practical applications, the authors say. The team plans to continue exploring the potential of this technique and related topological devices and possible ways to further improve the devices such as using other materials to make them.

    In addition to Hafezi and Mittal, former JQI graduate student Venkata Vikram Orre and former JQI postdoctoral researcher and current assistant professor at the University of Illinois Urbana-Champaign (US) Elizabeth Goldschmidt were also co-authors of the paper.

    See the full article here .


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    Stem Education Coalition

    JQI supported by Gordon and Betty Moore Foundation

    We are on the verge of a new technological revolution as the strange and unique properties of quantum physics become relevant and exploitable in the context of information science and technology.

    The Joint Quantum Institute (JQI) (US) is pursuing that goal through the work of leading quantum scientists from the Department of Physics of the University of Maryland (UMD (US)), the National Institute of Standards and Technology (NIST) and the Laboratory for Physical Sciences (LPS). Each institution brings to JQI major experimental and theoretical research programs that are dedicated to the goals of controlling and exploiting quantum systems.

    U Maryland Campus

    Driven by the pursuit of excellence, the University of Maryland (US) has enjoyed a remarkable rise in accomplishment and reputation over the past two decades. By any measure, Maryland is now one of the nation’s preeminent public research universities and on a path to become one of the world’s best. To fulfill this promise, we must capitalize on our momentum, fully exploit our competitive advantages, and pursue ambitious goals with great discipline and entrepreneurial spirit. This promise is within reach. This strategic plan is our working agenda.

    The plan is comprehensive, bold, and action oriented. It sets forth a vision of the University as an institution unmatched in its capacity to attract talent, address the most important issues of our time, and produce the leaders of tomorrow. The plan will guide the investment of our human and material resources as we strengthen our undergraduate and graduate programs and expand research, outreach and partnerships, become a truly international center, and enhance our surrounding community.

    Our success will benefit Maryland in the near and long term, strengthen the State’s competitive capacity in a challenging and changing environment and enrich the economic, social and cultural life of the region. We will be a catalyst for progress, the State’s most valuable asset, and an indispensable contributor to the nation’s well-being. Achieving the goals of Transforming Maryland requires broad-based and sustained support from our extended community. We ask our stakeholders to join with us to make the University an institution of world-class quality with world-wide reach and unparalleled impact as it serves the people and the state of Maryland.

     
  • richardmitnick 3:08 pm on May 9, 2021 Permalink | Reply
    Tags: "In graphene process resistance is useful", , , Laser Technology,   

    From Rice University (US) : “In graphene process resistance is useful” 


    From Rice University (US)

    May 6, 2021

    Jeff Falk
    713-348-6775
    jfalk@rice.edu

    Mike Williams
    713-348-6728
    mikewilliams@rice.edu

    Rice lab uses laser-induced graphene process to create micron-scale patterns in photoresist.

    1
    Rice University chemists have adapted their laser-induced graphene process to make conductive patterns from standard photoresist material for consumer electronics and other applications. Courtesy of the Tour Group.

    2
    Rice University graduate student Jacob Beckham shows a sample of photoresist laser-induced graphene, patterned in the shape of an owl. Photo by Aaron Bayles.

    A Rice University laboratory has adapted its laser-induced graphene technique to make high-resolution, micron-scale patterns of the conductive material for consumer electronics and other applications.

    Laser-induced graphene (LIG), introduced in 2014 by Rice chemist James Tour, involves burning away everything that isn’t carbon from polymers or other materials, leaving the carbon atoms to reconfigure themselves into films of characteristic hexagonal graphene.

    The process employs a commercial laser that “writes” graphene patterns into surfaces that to date have included wood, paper and even food.

    The new iteration writes fine patterns of graphene into photoresist polymers, light-sensitive materials used in photolithography and photoengraving. Baking the film increases its carbon content, and subsequent lasing solidifies the robust graphene pattern, after which unlased photoresist is washed away.

    Details of the PR-LIG process appear in the American Chemical Society journal ACS Nano.

    “This process permits the use of graphene wires and devices in a more conventional silicon-like process technology,” Tour said. “It should allow a transition into mainline electronics platforms.”

    The Rice lab produced lines of LIG about 10 microns wide and hundreds of nanometers thick, comparable to that now achieved by more cumbersome processes that involve lasers attached to scanning electron microscopes, according to the researchers.

    Achieving lines of LIG small enough for circuitry prompted the lab to optimize its process, according to graduate student Jacob Beckham, lead author of the paper.

    “The breakthrough was a careful control of the process parameters,” Beckham said. “Small lines of photoresist absorb laser light depending on their geometry and thickness, so optimizing the laser power and other parameters allowed us to get good conversion at very high resolution.”

    Because the positive photoresist is a liquid before being spun onto a substrate for lasing, it’s a simple matter to dope the raw material with metals or other additives to customize it for applications, Tour said.

    Potential applications include on-chip microsupercapacitors, functional nanocomposites and microfluidic arrays.

    Co-authors are undergraduate John Tianci Li, alumnus Michael Stanford and graduate students Weiyin Chen, Emily McHugh, Paul Advincula, Kevin Wyss and Yieu Chyan of Rice; and alumnus Walker Boldman and Philip Rack, a professor and Leonard G. Penland Chair of Materials Science and Engineering at the University of Tennessee (US), Knoxville. Tour is the T.T. and W.F. Chao Chair in Chemistry as well as a professor of computer science and of materials science and nanoengineering at Rice.

    4
    A scanning electron microscope image shows a cross-section of laser-induced graphene on silicon. The graphene was created at Rice University by lasing a photoresist polymer to make micron-scale lines that could be useful for electronics and other applications. The scale bar is 5 microns. Courtesy of the Tour Group.

    The Air Force Office of Science Research, the National Science Foundation and the Department of Energy supported the research.

    See the full article here .


    five-ways-keep-your-child-safe-school-shootings


    Stem Education Coalition

    Rice University (US) [formally William Marsh Rice University] is a private research university in Houston, Texas. It is situated on a 300-acre campus near the Houston Museum District and is adjacent to the Texas Medical Center.

    Opened in 1912 after the murder of its namesake William Marsh Rice, Rice is a research university with an undergraduate focus. Its emphasis on education is demonstrated by a small student body and 6:1 student-faculty ratio. The university has a very high level of research activity. Rice is noted for its applied science programs in the fields of artificial heart research, structural chemical analysis, signal processing, space science, and nanotechnology. Rice has been a member of the Association of American Universities (US) since 1985 and is classified among “R1: Doctoral Universities – Very high research activity”.

    The university is organized into eleven residential colleges and eight schools of academic study, including the Wiess School of Natural Sciences, the George R. Brown School of Engineering, the School of Social Sciences, School of Architecture, Shepherd School of Music and the School of Humanities. Rice’s undergraduate program offers more than fifty majors and two dozen minors, and allows a high level of flexibility in pursuing multiple degree programs. Additional graduate programs are offered through the Jesse H. Jones Graduate School of Business and the Susanne M. Glasscock School of Continuing Studies. Rice students are bound by the strict Honor Code, which is enforced by a student-run Honor Council.

    Rice competes in 14 NCAA Division I varsity sports and is a part of Conference USA, often competing with its cross-town rival the University of Houston. Intramural and club sports are offered in a wide variety of activities such as jiu jitsu, water polo, and crew.

    The university’s alumni include more than two dozen Marshall Scholars and a dozen Rhodes Scholars. Given the university’s close links to NASA, it has produced a significant number of astronauts and space scientists. In business, Rice graduates include CEOs and founders of Fortune 500 companies; in politics, alumni include congressmen, cabinet secretaries, judges, and mayors. Two alumni have won the Nobel Prize.

    Background

    Rice University’s history began with the demise of Massachusetts businessman William Marsh Rice, who had made his fortune in real estate, railroad development and cotton trading in the state of Texas. In 1891, Rice decided to charter a free-tuition educational institute in Houston, bearing his name, to be created upon his death, earmarking most of his estate towards funding the project. Rice’s will specified the institution was to be “a competitive institution of the highest grade” and that only white students would be permitted to attend. On the morning of September 23, 1900, Rice, age 84, was found dead by his valet, Charles F. Jones, and was presumed to have died in his sleep. Shortly thereafter, a large check made out to Rice’s New York City lawyer, signed by the late Rice, aroused the suspicion of a bank teller, due to the misspelling of the recipient’s name. The lawyer, Albert T. Patrick, then announced that Rice had changed his will to leave the bulk of his fortune to Patrick, rather than to the creation of Rice’s educational institute. A subsequent investigation led by the District Attorney of New York resulted in the arrests of Patrick and of Rice’s butler and valet Charles F. Jones, who had been persuaded to administer chloroform to Rice while he slept. Rice’s friend and personal lawyer in Houston, Captain James A. Baker, aided in the discovery of what turned out to be a fake will with a forged signature. Jones was not prosecuted since he cooperated with the district attorney, and testified against Patrick. Patrick was found guilty of conspiring to steal Rice’s fortune and he was convicted of murder in 1901 (he was pardoned in 1912 due to conflicting medical testimony). Baker helped Rice’s estate direct the fortune, worth $4.6 million in 1904 ($131 million today), towards the founding of what was to be called the Rice Institute, later to become Rice University. The board took control of the assets on April 29 of that year.

    In 1907, the Board of Trustees selected the head of the Department of Mathematics and Astronomy at Princeton University, Edgar Odell Lovett, to head the Institute, which was still in the planning stages. He came recommended by Princeton’s president, Woodrow Wilson. In 1908, Lovett accepted the challenge, and was formally inaugurated as the Institute’s first president on October 12, 1912. Lovett undertook extensive research before formalizing plans for the new Institute, including visits to 78 institutions of higher learning across the world on a long tour between 1908 and 1909. Lovett was impressed by such things as the aesthetic beauty of the uniformity of the architecture at the University of Pennsylvania, a theme which was adopted by the Institute, as well as the residential college system at Cambridge University in England, which was added to the Institute several decades later. Lovett called for the establishment of a university “of the highest grade,” “an institution of liberal and technical learning” devoted “quite as much to investigation as to instruction.” [We must] “keep the standards up and the numbers down,” declared Lovett. “The most distinguished teachers must take their part in undergraduate teaching, and their spirit should dominate it all.”

    Establishment and growth

    In 1911, the cornerstone was laid for the Institute’s first building, the Administration Building, now known as Lovett Hall in honor of the founding president. On September 23, 1912, the 12th anniversary of William Marsh Rice’s murder, the William Marsh Rice Institute for the Advancement of Letters, Science, and Art began course work with 59 enrolled students, who were known as the “59 immortals,” and about a dozen faculty. After 18 additional students joined later, Rice’s initial class numbered 77, 48 male and 29 female. Unusual for the time, Rice accepted coeducational admissions from its beginning, but on-campus housing would not become co-ed until 1957.

    Three weeks after opening, a spectacular international academic festival was held, bringing Rice to the attention of the entire academic world.

    Per William Marsh Rice’s will and Rice Institute’s initial charter, the students paid no tuition. Classes were difficult, however, and about half of Rice’s students had failed after the first 1912 term. At its first commencement ceremony, held on June 12, 1916, Rice awarded 35 bachelor’s degrees and one master’s degree. That year, the student body also voted to adopt the Honor System, which still exists today. Rice’s first doctorate was conferred in 1918 on mathematician Hubert Evelyn Bray.

    The Founder’s Memorial Statue, a bronze statue of a seated William Marsh Rice, holding the original plans for the campus, was dedicated in 1930, and installed in the central academic quad, facing Lovett Hall. The statue was crafted by John Angel. In 2020, Rice students petitioned the university to take down the statue due to the founder’s history as slave owner.

    During World War II, Rice Institute was one of 131 colleges and universities nationally that took part in the V-12 Navy College Training Program, which offered students a path to a Navy commission.

    The residential college system proposed by President Lovett was adopted in 1958, with the East Hall residence becoming Baker College, South Hall residence becoming Will Rice College, West Hall becoming Hanszen College, and the temporary Wiess Hall becoming Wiess College.

    In 1959, the Rice Institute Computer went online. 1960 saw Rice Institute formally renamed William Marsh Rice University. Rice acted as a temporary intermediary in the transfer of land between Humble Oil and Refining Company and NASA, for the creation of NASA’s Manned Spacecraft Center (now called Johnson Space Center) in 1962. President John F. Kennedy then made a speech at Rice Stadium reiterating that the United States intended to reach the moon before the end of the decade of the 1960s, and “to become the world’s leading space-faring nation”. The relationship of NASA with Rice University and the city of Houston has remained strong to the present day.

    The original charter of Rice Institute dictated that the university admit and educate, tuition-free, “the white inhabitants of Houston, and the state of Texas”. In 1963, the governing board of Rice University filed a lawsuit to allow the university to modify its charter to admit students of all races and to charge tuition. Ph.D. student Raymond Johnson became the first black Rice student when he was admitted that year. In 1964, Rice officially amended the university charter to desegregate its graduate and undergraduate divisions. The Trustees of Rice University prevailed in a lawsuit to void the racial language in the trust in 1966. Rice began charging tuition for the first time in 1965. In the same year, Rice launched a $33 million ($268 million) development campaign. $43 million ($283 million) was raised by its conclusion in 1970. In 1974, two new schools were founded at Rice, the Jesse H. Jones Graduate School of Management and the Shepherd School of Music. The Brown Foundation Challenge, a fund-raising program designed to encourage annual gifts, was launched in 1976 and ended in 1996 having raised $185 million. The Rice School of Social Sciences was founded in 1979.

    On-campus housing was exclusively for men for the first forty years, until 1957. Jones College was the first women’s residence on the Rice campus, followed by Brown College. According to legend, the women’s colleges were purposefully situated at the opposite end of campus from the existing men’s colleges as a way of preserving campus propriety, which was greatly valued by Edgar Odell Lovett, who did not even allow benches to be installed on campus, fearing that they “might lead to co-fraternization of the sexes”. The path linking the north colleges to the center of campus was given the tongue-in-cheek name of “Virgin’s Walk”. Individual colleges became coeducational between 1973 and 1987, with the single-sex floors of colleges that had them becoming co-ed by 2006. By then, several new residential colleges had been built on campus to handle the university’s growth, including Lovett College, Sid Richardson College, and Martel College.

    Late twentieth and early twenty-first century

    The Economic Summit of Industrialized Nations was held at Rice in 1990. Three years later, in 1993, the James A. Baker III Institute for Public Policy was created. In 1997, the Edythe Bates Old Grand Organ and Recital Hall and the Center for Nanoscale Science and Technology, renamed in 2005 for the late Nobel Prize winner and Rice professor Richard E. Smalley, were dedicated at Rice. In 1999, the Center for Biological and Environmental Nanotechnology was created. The Rice Owls baseball team was ranked #1 in the nation for the first time in that year (1999), holding the top spot for eight weeks.

    In 2003, the Owls won their first national championship in baseball, which was the first for the university in any team sport, beating Southwest Missouri State in the opening game and then the University of Texas and Stanford University twice each en route to the title. In 2008, President David Leebron issued a ten-point plan titled “Vision for the Second Century” outlining plans to increase research funding, strengthen existing programs, and increase collaboration. The plan has brought about another wave of campus constructions, including the erection the newly renamed BioScience Research Collaborative building (intended to foster collaboration with the adjacent Texas Medical Center), a new recreational center and the renovated Autry Court basketball stadium, and the addition of two new residential colleges, Duncan College and McMurtry College.

    Beginning in late 2008, the university considered a merger with Baylor College of Medicine, though the merger was ultimately rejected in 2010. Rice undergraduates are currently guaranteed admission to Baylor College of Medicine upon graduation as part of the Rice/Baylor Medical Scholars program. According to History Professor John Boles’ recent book University Builder: Edgar Odell Lovett and the Founding of the Rice Institute, the first president’s original vision for the university included hopes for future medical and law schools.

    In 2018, the university added an online MBA program, MBA@Rice.

    In June 2019, the university’s president announced plans for a task force on Rice’s “past in relation to slave history and racial injustice”, stating that “Rice has some historical connections to that terrible part of American history and the segregation and racial disparities that resulted directly from it”.

    Campus

    Rice’s campus is a heavily wooded 285-acre (115-hectare) tract of land in the museum district of Houston, located close to the city of West University Place.

    Five streets demarcate the campus: Greenbriar Street, Rice Boulevard, Sunset Boulevard, Main Street, and University Boulevard. For most of its history, all of Rice’s buildings have been contained within this “outer loop”. In recent years, new facilities have been built close to campus, but the bulk of administrative, academic, and residential buildings are still located within the original pentagonal plot of land. The new Collaborative Research Center, all graduate student housing, the Greenbriar building, and the Wiess President’s House are located off-campus.

    Rice prides itself on the amount of green space available on campus; there are only about 50 buildings spread between the main entrance at its easternmost corner, and the parking lots and Rice Stadium at the West end. The Lynn R. Lowrey Arboretum, consisting of more than 4000 trees and shrubs (giving birth to the legend that Rice has a tree for every student), is spread throughout the campus.

    The university’s first president, Edgar Odell Lovett, intended for the campus to have a uniform architecture style to improve its aesthetic appeal. To that end, nearly every building on campus is noticeably Byzantine in style, with sand and pink-colored bricks, large archways and columns being a common theme among many campus buildings. Noteworthy exceptions include the glass-walled Brochstein Pavilion, Lovett College with its Brutalist-style concrete gratings, Moody Center for the Arts with its contemporary design, and the eclectic-Mediterranean Duncan Hall. In September 2011, Travel+Leisure listed Rice’s campus as one of the most beautiful in the United States.

    Lovett Hall, named for Rice’s first president, is the university’s most iconic campus building. Through its Sallyport arch, new students symbolically enter the university during matriculation and depart as graduates at commencement. Duncan Hall, Rice’s computational engineering building, was designed to encourage collaboration between the four different departments situated there. The building’s foyer, drawn from many world cultures, was designed by the architect to symbolically express this collaborative purpose.

    The campus is organized in a number of quadrangles. The Academic Quad, anchored by a statue of founder William Marsh Rice, includes Ralph Adams Cram’s masterpiece, the asymmetrical Lovett Hall, the original administrative building; Fondren Library; Herzstein Hall; the original physics building and home to the largest amphitheater on campus; Sewall Hall for the social sciences and arts; Rayzor Hall for the languages; and Anderson Hall of the Architecture department. The Humanities Building winner of several architectural awards is immediately adjacent to the main quad. Further west lies a quad surrounded by McNair Hall of the Jones Business School; the Baker Institute; and Alice Pratt Brown Hall of the Shepherd School of Music. These two quads are surrounded by the university’s main access road, a one-way loop referred to as the “inner loop”. In the Engineering Quad, a trinity of sculptures by Michael Heizer, collectively entitled 45 Degrees; 90 Degrees; 180 Degrees are flanked by Abercrombie Laboratory; the Cox Building; and the Mechanical Laboratory housing the Electrical; Mechanical; and Earth Science/Civil Engineering departments respectively. Duncan Hall is the latest addition to this quad providing new offices for the Computer Science; Computational and Applied Math; Electrical and Computer Engineering; and Statistics departments.

    Roughly three-quarters of Rice’s undergraduate population lives on campus. Housing is divided among eleven residential colleges which form an integral part of student life at the university The colleges are named for university historical figures and benefactors.While there is wide variation in their appearance; facilities; and dates of founding are an important source of identity for Rice students functioning as dining halls; residence halls; sports teams among other roles. Rice does not have or endorse a Greek system with the residential college system taking its place. Five colleges: McMurtry; Duncan; Martel; Jones; and Brown are located on the north side of campus across from the “South Colleges”; Baker; Will Rice; Lovett, Hanszen; Sid Richardson; and Wiess on the other side of the Academic Quadrangle. Of the eleven colleges Baker is the oldest originally built in 1912 and the twin Duncan and McMurtry colleges are the newest and opened for the first time for the 2009–10 school year. Will Rice; Baker; and Lovett colleges are undergoing renovation to expand their dining facilities as well as the number of rooms available for students.

    The on-campus football facility-Rice Stadium opened in 1950 with a capacity of 70000 seats. After improvements in 2006 the stadium is currently configured to seat 47,000 for football but can readily be reconfigured to its original capacity of 70000, more than the total number of Rice alumni living and deceased. The stadium was the site of Super Bowl VIII and a speech by John F. Kennedy on September 12 1962 in which he challenged the nation to send a man to the moon by the end of the decade. The recently renovated Tudor Fieldhouse formerly known as Autry Court is home to the basketball and volleyball teams. Other stadia include the Rice Track/Soccer Stadium and the Jake Hess Tennis Stadium. A new Rec Center now houses the intramural sports offices and provide an outdoor pool and training and exercise facilities for all Rice students while athletics training will solely be held at Tudor Fieldhouse and the Rice Football Stadium.

    The university and Houston Independent School District jointly established The Rice School-a kindergarten through 8th grade public magnet school in Houston. The school opened in August 1994. Through Cy-Fair ISD Rice University offers a credit course based summer school for grades 8 through 12. They also have skills based classes during the summer in the Rice Summer School.

    Innovation District

    In early 2019 Rice announced the site where the abandoned Sears building in Midtown Houston stood along with its surrounding area would be transformed into the “The Ion” the hub of the 16-acre South Main Innovation District. President of Rice David Leebron stated “We chose the name Ion because it’s from the Greek ienai, which means ‘go’. We see it as embodying the ever-forward motion of discovery, the spark at the center of a truly original idea.”

    Students of Rice and other Houston-area colleges and universities making up the Student Coalition for a Just and Equitable Innovation Corridor are advocating for a Community Benefits Agreement (CBA)-a contractual agreement between a developer and a community coalition. Residents of neighboring Third Ward and other members of the Houston Coalition for Equitable Development Without Displacement (HCEDD) have faced consistent opposition from the City of Houston and Rice Management Company to a CBA as traditionally defined in favor of an agreement between the latter two entities without a community coalition signatory.

    Organization

    Rice University is chartered as a non-profit organization and is governed by a privately appointed board of trustees. The board consists of a maximum of 25 voting members who serve four-year terms. The trustees serve without compensation and a simple majority of trustees must reside in Texas including at least four within the greater Houston area. The board of trustees delegates its power by appointing a president to serve as the chief executive of the university. David W. Leebron was appointed president in 2004 and succeeded Malcolm Gillis who served since 1993. The provost six vice presidents and other university officials report to the president. The president is advised by a University Council composed of the provost, eight members of the Faculty Council, two staff members, one graduate student, and two undergraduate students. The president presides over a Faculty Council which has the authority to alter curricular requirements, establish new degree programs, and approve candidates for degrees.

    The university’s academics are organized into several schools. Schools that have undergraduate and graduate programs include:

    The Rice University School of Architecture
    The George R. Brown School of Engineering
    The School of Humanities
    The Shepherd School of Music
    The Wiess School of Natural Sciences
    The Rice University School of Social Sciences

    Two schools have only graduate programs:

    The Jesse H. Jones Graduate School of Management
    The Susanne M. Glasscock School of Continuing Studies

    Rice’s undergraduate students benefit from a centralized admissions process which admits new students to the university as a whole, rather than a specific school (the schools of Music and Architecture are decentralized). Students are encouraged to select the major path that best suits their desires; a student can later decide that they would rather pursue study in another field or continue their current coursework and add a second or third major. These transitions are designed to be simple at Rice with students not required to decide on a specific major until their sophomore year of study.

    Rice’s academics are organized into six schools which offer courses of study at the graduate and undergraduate level, with two more being primarily focused on graduate education, while offering select opportunities for undergraduate students. Rice offers 360 degrees in over 60 departments. There are 40 undergraduate degree programs, 51 masters programs, and 29 doctoral programs.

    Faculty members of each of the departments elect chairs to represent the department to each School’s dean and the deans report to the Provost who serves as the chief officer for academic affairs.

    Rice Management Company

    The Rice Management Company manages the $6.5 billion Rice University endowment (June 2019) and $957 million debt. The endowment provides 40% of Rice’s operating revenues. Allison Thacker is the President and Chief Investment Officer of the Rice Management Company, having joined the university in 2011.

    Academics

    Rice is a medium-sized highly residential research university. The majority of enrollments are in the full-time four-year undergraduate program emphasizing arts & sciences and professions. There is a high graduate coexistence with the comprehensive graduate program and a very high level of research activity. It is accredited by the Southern Association of Colleges and Schools as well as the professional accreditation agencies for engineering, management, and architecture.

    Each of Rice’s departments is organized into one of three distribution groups, and students whose major lies within the scope of one group must take at least 3 courses of at least 3 credit hours each of approved distribution classes in each of the other two groups, as well as completing one physical education course as part of the LPAP (Lifetime Physical Activity Program) requirement. All new students must take a Freshman Writing Intensive Seminar (FWIS) class, and for students who do not pass the university’s writing composition examination (administered during the summer before matriculation), FWIS 100, a writing class, becomes an additional requirement.

    The majority of Rice’s undergraduate degree programs grant B.S. or B.A. degrees. Rice has recently begun to offer minors in areas such as business, energy and water sustainability, and global health.

    Student body

    As of fall 2014, men make up 52% of the undergraduate body and 64% of the professional and post-graduate student body. The student body consists of students from all 50 states, including the District of Columbia, two U.S. Territories, and 83 foreign countries. Forty percent of degree-seeking students are from Texas.

    Research centers and resources

    Rice is noted for its applied science programs in the fields of nanotechnology, artificial heart research, structural chemical analysis, signal processing and space science.

    Rice Alliance for Technology and Entrepreneurship – supports entrepreneurs and early-stage technology ventures in Houston and Texas through education, collaboration, and research, ranked No. 1 among university business incubators.
    Baker Institute for Public Policy – a leading nonpartisan public policy think-tank
    BioScience Research Collaborative (BRC) – interdisciplinary, cross-campus, and inter-institutional resource between Rice University and Texas Medical Center
    Boniuk Institute – dedicated to religious tolerance and advancing religious literacy, respect and mutual understanding
    Center for African and African American Studies – fosters conversations on topics such as critical approaches to race and racism, the nature of diasporic histories and identities, and the complexity of Africa’s past, present and future
    Chao Center for Asian Studies – research hub for faculty, students and post-doctoral scholars working in Asian studies
    Center for the Study of Women, Gender, and Sexuality (CSWGS) – interdisciplinary academic programs and research opportunities, including the journal Feminist Economics
    Data to Knowledge Lab (D2K) – campus hub for experiential learning in data science
    Digital Signal Processing (DSP) – center for education and research in the field of digital signal processing
    Ethernest Hackerspace – student-run hackerspace for undergraduate engineering students sponsored by the ECE department and the IEEE student chapter
    Humanities Research Center (HRC) – identifies, encourages, and funds innovative research projects by faculty, visiting scholars, graduate, and undergraduate students in the School of Humanities and beyond
    Institute of Biosciences and Bioengineering (IBB) – facilitates the translation of interdisciplinary research and education in biosciences and bioengineering
    Ken Kennedy Institute for Information Technology – advances applied interdisciplinary research in the areas of computation and information technology
    Kinder Institute for Urban Research – conducts the Houston Area Survey, “the nation’s longest running study of any metropolitan region’s economy, population, life experiences, beliefs and attitudes”
    Laboratory for Nanophotonics (LANP) – a resource for education and research breakthroughs and advances in the broad, multidisciplinary field of nanophotonics
    Moody Center for the Arts – experimental arts space featuring studio classrooms, maker space, audiovisual editing booths, and a gallery and office space for visiting national and international artists
    OpenStax CNX (formerly Connexions) and OpenStax – an open source platform and open access publisher, respectively, of open educational resources
    Oshman Engineering Design Kitchen (OEDK) – space for undergraduate students to design, prototype and deploy solutions to real-world engineering challenges
    Rice Cinema – an independent theater run by the Visual and Dramatic Arts department at Rice which screens documentaries, foreign films, and experimental cinema and hosts film festivals and lectures since 1970
    Rice Center for Engineering Leadership (RCEL) – inspires, educates, and develops ethical leaders in technology who will excel in research, industry, non-engineering career paths, or entrepreneurship
    Religion and Public Life Program (RPLP) – a research, training and outreach program working to advance understandings of the role of religion in public life
    Rice Design Alliance (RDA) – outreach and public programs of the Rice School of Architecture
    Rice Center for Quantum Materials (RCQM) – organization dedicated to research and higher education in areas relating to quantum phenomena
    Rice Neuroengineering Initiative (NEI) – fosters research collaborations in neural engineering topics
    Rice Space Institute (RSI) – fosters programs in all areas of space research
    Smalley-Curl Institute for Nanoscale Science and Technology (SCI) – the nation’s first nanotechnology center
    Welch Institute for Advanced Materials – collaborative research institute to support the foundational research for discoveries in materials science, similar to the model of Salk Institute and Broad Institute
    Woodson Research Center Special Collections & Archives – publisher of print and web-based materials highlighting the department’s primary source collections such as the Houston African American, Asian American, and Jewish History Archives, University Archives, rare books, and hip hop/rap music-related materials from the Swishahouse record label and Houston Folk Music Archive, etc.

    Student life

    Situated on nearly 300 acres (120 ha) in the center of Houston’s Museum District and across the street from the city’s Hermann Park, Rice is a green and leafy refuge; an oasis of learning convenient to the amenities of the nation’s fourth-largest city. Rice’s campus adjoins Hermann Park, the Texas Medical Center, and a neighborhood commercial center called Rice Village. Hermann Park includes the Houston Museum of Natural Science, the Houston Zoo, Miller Outdoor Theatre and an 18-hole municipal golf course. NRG Park, home of NRG Stadium and the Astrodome, is two miles (3 km) south of the campus. Among the dozen or so museums in the Museum District was (until May 14, 2017) the Rice University Art Gallery, open during the school year from 1995 until it closed in 2017. Easy access to downtown’s theater and nightlife district and to Reliant Park is provided by the Houston METRORail system, with a station adjacent to the campus’s main gate. The campus recently joined the Zipcar program with two vehicles to increase the transportation options for students and staff who need but currently don’t utilize a vehicle.

    Residential colleges

    In 1957, Rice University implemented a residential college system, which was proposed by the university’s first president, Edgar Odell Lovett. The system was inspired by existing systems in place at Oxford(UK) and Cambridge(UK) and at several other universities in the United States, most notably Yale University. The existing residences known as East, South, West, and Wiess Halls became Baker, Will Rice, Hanszen, and Wiess Colleges, respectively.

    List of residential colleges:

    Baker College, named in honor of Captain James A. Baker, friend and attorney of William Marsh Rice, and first chair of the Rice Board of Governors.
    Will Rice College, named for William M. Rice, Jr., the nephew of the university’s founder, William Marsh Rice.
    Hanszen College, named for Harry Clay Hanszen, benefactor to the university and chairman of the Rice Board of Governors from 1946 to 1950.
    Wiess College, named for Harry Carothers Wiess (1887–1948), one of the founders and one-time president of Humble Oil, now ExxonMobil.
    Jones College, named for Mary Gibbs Jones, wife of prominent Houston philanthropist Jesse Holman Jones.
    Brown College, named for Margaret Root Brown by her in-laws, George R. Brown.
    Lovett College, named after the university’s first president, Edgar Odell Lovett.
    Sid Richardson College, named for the Sid Richardson Foundation, which was established by Texas oilman, cattleman, and philanthropist Sid W. Richardson.
    Martel College, named for Marian and Speros P. Martel, was built in 2002.
    McMurtry College, named for Rice alumni Burt and Deedee McMurtry, Silicon Valley venture capitalists.
    Duncan College, named for Charles Duncan, Jr., Secretary of Energy.

    Much of the social and academic life as an undergraduate student at Rice is centered around residential colleges. Each residential college has its own cafeteria (serveries) and each residential college has study groups and its own social practices.

    Although each college is composed of a full cross-section of students at Rice, they have over time developed their own traditions and “personalities”. When students matriculate they are randomly assigned to one of the eleven colleges, although “legacy” exceptions are made for students whose siblings or parents have attended Rice. Students generally remain members of the college that they are assigned to for the duration of their undergraduate careers, even if they move off-campus at any point. Students are guaranteed on-campus housing for freshman year and two of the next three years; each college has its own system for determining allocation of the remaining spaces, collectively known as “Room Jacking”. Students develop strong loyalties to their college and maintain friendly rivalry with other colleges, especially during events such as Beer Bike Race and O-Week. Colleges keep their rivalries alive by performing “jacks,” or pranks, on each other, especially during O-Week and Willy Week. During Matriculation, Commencement, and other formal academic ceremonies, the colleges process in the order in which they were established.

    Student-run media

    Rice has a weekly student newspaper (The Rice Thresher), a yearbook (The Campanile), college radio station (KTRU Rice Radio), and now defunct, campus-wide student television station (RTV5). They are based out of the RMC student center. In addition, Rice hosts several student magazines dedicated to a range of different topics; in fact, the spring semester of 2008 saw the birth of two such magazines, a literary sex journal called Open and an undergraduate science research magazine entitled Catalyst.

    The Rice Thresher is published every Wednesday and is ranked by Princeton Review as one of the top campus newspapers nationally for student readership. It is distributed around campus, and at a few other local businesses and has a website. The Thresher has a small, dedicated staff and is known for its coverage of campus news, open submission opinion page, and the satirical Backpage, which has often been the center of controversy. The newspaper has won several awards from the College Media Association, Associated Collegiate Press and Texas Intercollegiate Press Association.

    The Rice Campanile was first published in 1916 celebrating Rice’s first graduating class. It has published continuously since then, publishing two volumes in 1944 since the university had two graduating classes due to World War II. The website was created sometime in the early to mid 2000s. The 2015 won the first place Pinnacle for best yearbook from College Media Association.

    KTRU Rice Radio is the student-run radio station. Though most DJs are Rice students, anyone is allowed to apply. It is known for playing genres and artists of music and sound unavailable on other radio stations in Houston, and often, the US. The station takes requests over the phone or online. In 2000 and 2006, KTRU won Houston Press’ Best Radio Station in Houston. In 2003, Rice alum and active KTRU DJ DL’s hip-hip show won Houston Press‘ Best Hip-hop Radio Show. On August 17, 2010, it was announced that Rice University had been in negotiations to sell the station’s broadcast tower, FM frequency and license to the University of Houston System to become a full-time classical music and fine arts programming station. The new station, KUHA, would be operated as a not-for-profit outlet with listener supporters. The FCC approved the sale and granted the transfer of license to the University of Houston System on April 15, 2011, however, KUHA proved to be an even larger failure and so after four and a half years of operation, The University of Houston System announced that KUHA’s broadcast tower, FM frequency and license were once again up for sale in August 2015. KTRU continued to operate much as it did previously, streaming live on the Internet, via apps, and on HD2 radio using the 90.1 signal. Under student leadership, KTRU explored the possibility of returning to FM radio for a number of years. In spring 2015, KTRU was granted permission by the FCC to begin development of a new broadcast signal via LPFM radio. On October 1, 2015, KTRU made its official return to FM radio on the 96.1 signal. While broadcasting on HD2 radio has been discontinued, KTRU continues to broadcast via internet in addition to its LPFM signal.

    RTV5 is a student-run television network available as channel 5 on campus. RTV5 was created initially as Rice Broadcast Television in 1997; RBT began to broadcast the following year in 1998, and aired its first live show across campus in 1999. It experienced much growth and exposure over the years with successful programs like Drinking with Phil, The Meg & Maggie Show, which was a variety and call-in show, a weekly news show, and extensive live coverage in December 2000 of the shut down of KTRU by the administration. In spring 2001, the Rice undergraduate community voted in the general elections to support RBT as a blanket tax organization, effectively providing a yearly income of $10,000 to purchase new equipment and provide the campus with a variety of new programming. In the spring of 2005, RBT members decided the station needed a new image and a new name: Rice Television 5. One of RTV5’s most popular shows was the 24-hour show, where a camera and couch placed in the RMC stayed on air for 24 hours. One such show is held in fall and another in spring, usually during a weekend allocated for visits by prospective students. RTV5 has a video on demand site at rtv5.rice.edu. The station went off the air in 2014 and changed its name to Rice Video Productions. In 2015 the group’s funding was threatened, but ultimately maintained. In 2016 the small student staff requested to no longer be a blanket-tax organization. In the fall of 2017, the club did not register as a club.

    The Rice Review, also known as R2, is a yearly student-run literary journal at Rice University that publishes prose, poetry, and creative nonfiction written by undergraduate students, as well as interviews. The journal was founded in 2004 by creative writing professor and author Justin Cronin.

    The Rice Standard was an independent, student-run variety magazine modeled after such publications as The New Yorker and Harper’s. Prior to fall 2009, it was regularly published three times a semester with a wide array of content, running from analyses of current events and philosophical pieces to personal essays, short fiction and poetry. In August 2009, The Standard transitioned to a completely online format with the launch of their redesigned website, http://www.ricestandard.org. The first website of its kind on Rice’s campus, The Standard featured blog-style content written by and for Rice students. The Rice Standard had around 20 regular contributors, and the site features new content every day (including holidays). In 2017 no one registered The Rice Standard as a club within the university.

    Open, a magazine dedicated to “literary sex content,” predictably caused a stir on campus with its initial publication in spring 2008. A mixture of essays, editorials, stories and artistic photography brought Open attention both on campus and in the Houston Chronicle. The third and last annual edition of Open was released in spring of 2010.

    Vahalla is the Graduate Student Association on-campus bar under the steps of the chemistry building.

    Athletics

    Rice plays in NCAA Division I athletics and is part of Conference USA. Rice was a member of the Western Athletic Conference before joining Conference USA in 2005. Rice is the second-smallest school, measured by undergraduate enrollment, competing in NCAA Division I FBS football, only ahead of Tulsa.

    The Rice baseball team won the 2003 College World Series, defeating Stanford, giving Rice its only national championship in a team sport. The victory made Rice University the smallest school in 51 years to win a national championship at the highest collegiate level of the sport. The Rice baseball team has played on campus at Reckling Park since the 2000 season. As of 2010, the baseball team has won 14 consecutive conference championships in three different conferences: the final championship of the defunct Southwest Conference, all nine championships while a member of the Western Athletic Conference, and five more championships in its first five years as a member of Conference USA. Additionally, Rice’s baseball team has finished third in both the 2006 and 2007 College World Series tournaments. Rice now has made six trips to Omaha for the CWS. In 2004, Rice became the first school ever to have three players selected in the first eight picks of the MLB draft when Philip Humber, Jeff Niemann, and Wade Townsend were selected third, fourth, and eighth, respectively. In 2007, Joe Savery was selected as the 19th overall pick.

    Rice has been very successful in women’s sports in recent years. In 2004–05, Rice sent its women’s volleyball, soccer, and basketball teams to their respective NCAA tournaments. The women’s swim team has consistently brought at least one member of their team to the NCAA championships since 2013. In 2005–06, the women’s soccer, basketball, and tennis teams advanced, with five individuals competing in track and field. In 2006–07, the Rice women’s basketball team made the NCAA tournament, while again five Rice track and field athletes received individual NCAA berths. In 2008, the women’s volleyball team again made the NCAA tournament. In 2011 the Women’s Swim team won their first conference championship in the history of the university. This was an impressive feat considering they won without having a diving team. The team repeated their C-USA success in 2013 and 2014. In 2017, the women’s basketball team, led by second-year head coach Tina Langley, won the Women’s Basketball Invitational, defeating UNC-Greensboro 74–62 in the championship game at Tudor Fieldhouse. Though not a varsity sport, Rice’s ultimate frisbee women’s team, named Torque, won consecutive Division III national championships in 2014 and 2015.

    In 2006, the football team qualified for its first bowl game since 1961, ending the second-longest bowl drought in the country at the time. On December 22, 2006, Rice played in the New Orleans Bowl in New Orleans, Louisiana against the Sun Belt Conference champion, Troy. The Owls lost 41–17. The bowl appearance came after Rice had a 14-game losing streak from 2004–05 and went 1–10 in 2005. The streak followed an internally authorized 2003 McKinsey report that stated football alone was responsible for a $4 million deficit in 2002. Tensions remained high between the athletic department and faculty, as a few professors who chose to voice their opinion were in favor of abandoning the football program. The program success in 2006, the Rice Renaissance, proved to be a revival of the Owl football program, quelling those tensions. David Bailiff took over the program in 2007 and has remained head coach. Jarett Dillard set an NCAA record in 2006 by catching a touchdown pass in 13 consecutive games and took a 15-game overall streak into the 2007 season.

    In 2008, the football team posted a 9-3 regular season, capping off the year with a 38–14 victory over Western Michigan University in the Texas Bowl. The win over Western Michigan marked the Owls’ first bowl win in 45 years.

    Rice Stadium also serves as the performance venue for the university’s Marching Owl Band, or “MOB.” Despite its name, the MOB is a scatter band that focuses on performing humorous skits and routines rather than traditional formation marching.

    Rice Owls men’s basketball won 10 conference titles in the former Southwest Conference (1918, 1935*, 1940, 1942*, 1943*, 1944*, 1945, 1949*, 1954*, 1970; * denotes shared title). Most recently, guard Morris Almond was drafted in the first round of the 2007 NBA Draft by the Utah Jazz. Rice named former Cal Bears head coach Ben Braun as head basketball coach to succeed Willis Wilson, fired after Rice finished the 2007–2008 season with a winless (0-16) conference record and overall record of 3-27.

    Rice’s mascot is Sammy the Owl. In previous decades, the university kept several live owls on campus in front of Lovett College, but this practice has been discontinued, due to public pressure over the welfare of the owls.

    Rice also has a 12-member coed cheerleading squad and a coed dance team, both of which perform at football and basketball games throughout the year.

     
  • richardmitnick 11:07 am on May 8, 2021 Permalink | Reply
    Tags: , , Carl von Ossietzky University of Oldenburg [Carl von Ossietzky Universität Oldenburg] (DE), Exciton-polaritons combine interesting properties of electrons and photons and behave in a similar way to certain physical particles called bosons., Laser Technology, , The study focuses on quasi particles consisting of both matter and light known as exciton-polaritons – a strong couplings between excited electrons in solids and light particles (photons).   

    From Carl von Ossietzky University of Oldenburg [Carl von Ossietzky Universität Oldenburg] (DE): “Homing in on the smallest possible laser” 

    From Carl von Ossietzky University of Oldenburg [Carl von Ossietzky Universität Oldenburg] (DE)

    05/06/2021

    1
    A cage for light: a two-dimensional crystal (middle) was placed between two layers of mirror-like materials. When cooled to a few degrees above absolute zero and stimulated by short pulses of laser light above a certain theshold, the crystals began to emit coherent light (red). The researchers concluded that a Bose-Einstein Condensate out of exciton-polaritons had formed. Graphics: Johannes Michl.

    An international team of researchers led by Oldenburg physicists has succeeded in generating an unusual quantum state in ultrathin semiconductor sheets. The team reports in Nature Materials that this process produces light similar to that of a laser.

    At extremely low temperatures, matter often behaves differently than in normal conditions. At temperatures only a few degrees above absolute zero (-273 degrees Celsius), physical particles may give up their independence and merge for a short time into a single object in which all the particles share the same properties. Such structures are known as Bose-Einstein Condensates, and they represent a special aggregate state of matter.

    An international team of researchers led by Oldenburg physicists Dr Carlos Anton-Solanas and Professor Christian Schneider has now succeeded for the first time in generating this unusual quantum state in charge carrier complexes that are closely linked to light particles and located in ultrathin semiconductor sheets consisting of a single layer of atoms. As the team reports in the scientific journal Nature Materials, this process produces light similar to that generated by a laser. This means that the phenomenon could be used to create the smallest possible solid-state lasers.

    The work is the result of a collaboration between the Oldenburg researchers and the research groups of Professor Sven Höfling and Professor Sebastian Klembt from the Julius Maximilian University of Würzburg [Julius-Maximilians-Universität Würzburg] (DE), Professor Sefaattin Tongay from Arizona State University (US), Professor Alexey Kavokin from Westlake University [西湖大学] (CN), and Professor Takashi Taniguchi and Professor Kenji Watanabe from the NIMS National Institute for Materials Science [物質・材料研究機構] (JP).

    Quasi particles made of matter and light

    The study focuses on quasi particles that consist of both matter and light known as exciton-polaritons – the product of strong couplings between excited electrons in solids and light particles (photons). They form when electrons are stimulated by laser light into a higher energy state. After a short time in the order of one trillionth of a second, the electrons return to their ground state by re-emitting light particles. When these particles are trapped between two mirrors, they can in turn excite new electrons – a cycle that repeats until the light particle escapes the trap. The light-matter hybrid particles that are created in this process are called exciton-polaritons.

    They combine interesting properties of electrons and photons and behave in a similar way to certain physical particles called bosons. “Devices that can control these novel light-matter states hold the promise of a technological leap in comparison with current electronic circuits,” said lead author Anton-Solanas, a postdoctoral researcher in the Quantum Materials Group at the University of Oldenburg’s Institute of Physics. Such optoelectronic circuits, which operate using light instead of electric current, could be better and faster at processing information than today’s processors.

    In the new study, the team led by Anton-Solanas and Schneider looked at exciton-polaritons in ultrathin crystals consisting of a single layer of atoms. These two-dimensional crystals often have unusual physical properties. For example, the semiconductor material used here, molybdenum diselenide, is highly reactive to light. The researchers constructed sheets of molybdenum diselenide less than one nanometre (a billionth of a metre) thick and sandwiched the two-dimensional crystal between two layers of other materials that reflect light particles like mirrors do. “This structure acts like a cage for light,” Anton-Solanas explained. Physicists call it a “microcavity”.

    Coherent light sources based on just a single layer of atoms

    Anton-Solanas and his colleagues cooled their setup to a few degrees above absolute zero and stimulated the formation of exciton-polaritons using short pulses of laser light. Above a certain intensity they observed a sudden increase in the light emissions from their sample. This, together with other evidence, allowed them to conclude that they had succeeded in creating a Bose-Einstein Condensate out of exciton-polaritons. “In theory, this phenomenon could be used to construct coherent light sources based on just a single layer of atoms,” said Anton-Solanas. “This would mean we had created the smallest possible solid-state laser.” The researchers are confident that with other materials the effect could also be produced at room temperature, so that in the long term it would also be suitable for practical applications. The team’s first experiments heading in this direction have already been successful.

    The study is a result of the “unlimit2D” project led by Christian Schneider, which is funded by a Starting Grant from the European Research Council (ERC) (EU). The experiments were conducted at the University of Würzburg

    See the full article here.

    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    The Carl von Ossietzky University of Oldenburg [Carl von Ossietzky Universität Oldenburg] is a university located in Oldenburg, Germany. It is one of the most important and highly regarded educational facilities in northwestern Germany and specialises in interdisciplinary and sustainable development studies and renewable energy studies with focus on solar and wind energy.

    The university offers 95 courses of study. Due to the Bologna Process, in 2004 Oldenburg adopted Bachelor and Masters degrees in place of the former Diplom and Magister. One main focus of the university is teacher training, which was established during the 1970s and remains a strong presence with master’s degrees in teaching offered in all faculties. The PhD program Didactical reconstruction is especially renowned, as is the research in sustainable development, encompassing several academic disciplines. The university is also allowed to confer Doctorates and oversee Habilitations.

    The campus is split into two locations, the major one being Uhlhornsweg, where the main library, the mensa and the administration along with most of the departments is housed. Having used the buildings of the former teaching college during the first years, the main buildings of the university were inaugurated in 1982, with ongoing extensions since then, including the main lecture hall in 2001. The Wechloy campus, also first opened in 1982, is home to the studies of natural sciences as well as the library of natural sciences.

    As part of the Universities Excellence Initiative, the university was awarded a Cluster of Excellence for its initiative Hearing4all. The cluster deals with research into the improvement of speech understanding in background noise and has a funding of €34 million.

     
  • richardmitnick 7:50 pm on May 6, 2021 Permalink | Reply
    Tags: "Realization of the highest laser intensity ever reached", , , Laser Technology   

    From Institute for Basic Science [ 기초과학연구원](KR): “Realization of the highest laser intensity ever reached” 

    From Institute for Basic Science [ 기초과학연구원](KR)

    The record-breaking laser intensity over 10^23 W/cm^2 enables us to explore novel physical phenomena occurring under extreme physical conditions

    1
    ▲ Figure 1. Layout of the CoReLS petawatt laser and the experimental setup to achieve the laser intensity of over 10^23W/cm^2. BS, beam splitter; DM1-2, deformable mirrors; EM, energy meter; OAP, f /1.1 off-axis parabolic mirror; OL, objective lens; WFS1-2, wavefront sensors.

    2
    ▲ Figure 2. Panoramic view of the CoReLS PW laser.

    3
    ▲ Figure 3. Measured 3-D focal spot image showing the laser intensity of 1.4×10^23 W/cm^2.

    Recently, laser scientists at the Center for Relativistic Laser Science (CoReLS) within the Institute for Basic Science (IBS) in South Korea realized the unprecedented laser intensity of 10^23 W/cm^2. This has been a milestone that has been pursued for almost two decades by many laser institutes around the world.

    An ultrahigh intensity laser is an important research tool in several fields of science, including those which explore novel physical phenomena occurring under extreme physical conditions. Since the demonstration of the 10^22 W/cm^2 intensity laser by a team at the University of Michigan (US) in 2004, the realization of laser intensity over 10^23 W/cm^2 has been pursued for nearly 20 years.

    In general, achieving such a level of ultra-high laser intensity requires two things: laser with extremely high power output, and focusing that laser to the smallest spot as possible. While continuous-wave lasers are limited to megawatt-scale intensity, far higher peak power output (on the order of petawatt) is possible in pulsed laser systems by delivering the energy in the time scale as short as femtoseconds. In order to reach the goal of developing the world’s most powerful laser, several ultrahigh power laser facilities with outputs of 10 PW and beyond, such as ELI (EU), Apollon (France), EP-OPAL (USA), and SEL (China), have been built or are being planned. A recent study from Osaka University (JP) even proposed a concept prototype for an exawatt class laser.

    Meanwhile, the CoReLS laser team has been operating a 4-PW laser system since 2016. This year in April 2021, they have finally achieved the record-breaking milestone of 10^23 W/cm^2 by tightly focusing the multi-PW laser beam.

    Several special techniques have been employed to achieve this feat. The power intensity was maximized by using a focusing optics called an off-axis parabolic mirror, which was used to focus a 28 cm laser beam down to a spot only 1.1 micrometers wide. Such a diffraction-limited tight focusing can be obtained only with a clean laser beam without wavefront distortion. The CoReLS laser team, thus, made its PW laser beam as clean as possible using a set of deformable mirrors to correct the wavefront distortion of the PW laser.

    The CoReLS 4-PW laser is a femtosecond, ultrahigh power Ti:sapphire laser, based on the chirped pulse amplification (CPA) technique. The layout of the CoReLS 4-PW laser, including the experimental setup to control the wavefront and to measure the intensity, is given in Fig. 1. A low-energy femtosecond laser pulse from the front-end was stretched to a nanosecond pulse by the pulse stretcher. The initial laser pulse was then amplified to 4.5 J by the two power amplifiers and then up to 112 J by the two booster amplifiers. The size of the laser beam increased along the beam path by a series of beam expanders; 25 mm right after the power amplifiers, 65 mm at the entrance of the 1st booster amplifier, 85 mm at the entrance of the 2nd booster amplifier, and 280 mm at the entrance of the pulse compressor. In the pulse compressor, the laser pulse was recompressed to 20 fs (FWHM), which caused its peak power to become 4 PW after the compression.

    In order to compensate for the wavefront distortion of the PW laser beam, two deformable mirrors were employed in the PW laser beamline. The first deformable mirror (DM1) with a diameter of 100 mm was installed after the final booster amplifier, with its role being to correct the wavefront distortion accumulated from the front end to the final beam expander. The second deformable mirror (DM2) with a diameter of 310 mm was installed after the pulse compressor, which corrects the additional aberrations induced from large aperture optics in the pulse compressor, the beam delivery line, and the target area. In the target chamber, the PW laser beam was tightly focused with an f /1.1 off-axis parabolic mirror, which possessed an effective focal length of 300 mm. For imaging and characterization of the focused spot, the focused beam was collimated by an objective lens. It was then divided into two beams with a beam splitter for the focal spot and wavefront characterization. A camera was used for the focal spot monitoring of the transmitted laser beam, and a wavefront sensor was used to measure the wavefront of the reflected laser beam. Figure 3 shows the 3-D focal spot image measured by the camera in the target chamber.

    Prof. NAM Chang Hee, the Director of CoReLS, notes, “This work has shown that the CoReLS PW laser is the most powerful laser in the world. With the highest laser intensity achieved ever, we can tackle new challenging areas of experimental science, especially strong field quantum electrodynamics (QED) that has been dealt with mainly by theoreticians. We can explore new physical problems of electron-photon scattering (Compton scattering) and photon-photon scattering (Breit-Wheeler process) in the nonlinear regime. This kind of research is directly related to various astrophysical phenomena occurring in the universe and can help us to further expand our knowledge horizon.”

    Science paper:
    Optica

    See the full article here .

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    Please help promote STEM in your local schools.

    Stem Education Coalition

    Making Discoveries for Humanity & Society

    Institute for Basic Science [ 기초과학연구원](KR) pursues excellence in basic science research. The goal of IBS is to advance the frontiers of knowledge and to train the leading scientists of tomorrow.

    Accelerate Transformation through New Knowledge

    Institute for Basic Science [ 기초과학연구원](KR) was established in November 2011 as Korea’s first dedicated basic science research institute. By studying the fundamental principles of nature, basic science is essential in creating new knowledge from which significant societal transformations are derived. IBS promotes the highest quality of research that will increase the national basic science capacity and generate new opportunities for this nation.

    IBS specializes in long-term projects that require large groups of researchers. As research in the 21st century requires more interdisciplinary collaborations from larger groups of people, scientists at IBS work together in the same laboratory base with a long-term perspective on research. We promote autonomy in research. IBS believes scientists unleash their creative potential most effectively when they conduct research in an autonomous environment with world-class research infrastructure, including RISP, the rare isotope accelerator, to enable major scientific advances. By developing strong synergies from outstanding talents, autonomous research support systems, and world-class infrastructure, IBS is steadily growing into a major basic research institute that meets the global standards of excellence.
    Ensure Excellence in Research

    By pursuing excellence in research, IBS has selected global leading scientists as directors of Centers. These directors are operating 31 Centers of which research proposals are evaluated superior in the IBS peer review process. The review is carried out by a Review Panel composed of independent and expert scientists from Korea and abroad. Directors choose the themes of their research and allocate funds accordingly. Generally, Centers operate projects with no fixed term for their duration as long as the quality of research is verified in evaluations. New Centers receive an initial evaluation five years after its launch, followed by three-year interval evaluations.

    IBS has been inviting top scientists from around the globe and providing them full support for their relocations. Young scientists also enjoy unique research opportunities to collaborate with world renowned scientists and to organize and operate their own research groups, broadening their professional expertise. IBS brings together outstanding talents throughout all career levels to grow and inspire each other through close collaborations.

    Stimulate Collaboration Without Boundaries

    IBS welcomes scientists from Korea and abroad seeking to work in a collaborative research environment. IBS’ faculty researcher program and IBS’s affiliation with the founding body of University of Science & Technology [과학 기술 연합 대학원대학교] (KR) help IBS scientists to reach out to and foster young talent outside the institution. Centers serve as a catalyst for research collaboration with universities and other government-funded research institutions through joint research and the sharing of research equipment. Other efforts are also underway to stimulate collaborations, including overseas training programs and visiting scientist programs.

    To disseminate research findings, IBS holds “IBS Conferences” and develops a global network with the world’s prominent research institutions including the MPG Society for the Advancement of Science [MPG Gesellschaft zur Förderung der Wissenschaften e. V.] (DE) and the Royal Society (UK). We expect our work to make transformative changes outside as well as inside the institution. To realize this exciting vision, IBS will serve as a national R&D platform and accelerate the creation and use of new knowledge to support universities, research institutions, and businesses. As a driving force for dynamic research collaborations, IBS will continually develop and refresh its science, while always remaining receptive to outside talents and ideas.
    Continue its Endeavor to Make a Brighter Future

    IBS shares the same passion as other great minds to investigate the origin of the universe, nature, and life for the development of humanity, as shown in its vision Masking Discoveries for Humanity & Society. We are committed to realizing this vision through a phased endeavor as outlined in our Five-year Plan (2013 – 2017). We aim to:

    Become a national hub for basic science research by 2017
    Complete the construction of the rare isotope accelerator by 2021
    Evolve into one of the world’s top 20 basic research institution by 2030 (measured in terms of impact on research).

    Serving as a stimulus for the innovation, IBS HQ will evolve into an urban science park that will promote public outreach and community engagement. Our commitment to enhance the quality of life and make sustainable progress continues every day.

     
  • richardmitnick 12:43 pm on May 6, 2021 Permalink | Reply
    Tags: , , Laser Technology, , , University of Oldenburg [Carl von Ossietzky Universität Oldenburg] (DE)   

    From phys.org : “Homing in on the smallest possible laser” 

    From phys.org

    1
    In their experiments, the resesearchers used ultrathin crystals consisting of a single layer of atoms. These sheet was sandwiched between two layers of mirror-like materials. The whole structure acts like a cage for light and is called a “microcavity”. This setup was cooled to a few degrees above absolute zero. The researchers stimulated the crystal in the middle by short pulses of laser light (not shown). A sudden increase in the light emissions from the sample (red) indicated that a Bose-Einstein Condensate out of exciton-polaritons had been formed. Credit: Johannes Michl.

    At extremely low temperatures, matter often behaves differently than in normal conditions. At temperatures only a few degrees above absolute zero (-273 degrees Celsius), physical particles may give up their independence and merge for a short time into a single object in which all the particles share the same properties. Such structures are known as Bose-Einstein Condensates, and they represent a special aggregate state of matter.

    An international team of researchers led by physicists Dr. Carlos Anton-Solanas and Professor Christian Schneider from the University of Oldenburg [Carl von Ossietzky Universität Oldenburg] (DE) has now succeeded for the first time in generating this unusual quantum state in charge carrier complexes that are closely linked to light particles and located in ultrathin semiconductor sheets consisting of a single layer of atoms. As the team reports in the scientific journal Nature Materials, this process produces light similar to that generated by a laser. This means that the phenomenon could be used to create the smallest possible solid-state lasers.

    The work is the result of a collaboration between the Oldenburg researchers and the research groups of Professor Sven Höfling and Professor Sebastian Klembt from the University of Oldenburg [Carl von Ossietzky Universität Oldenburg] (DE), Professor Sefaattin Tongay from Arizona State University (U.S.), Professor Alexey Kavokin from Westlake University [ 西湖大学] (CN) , and Professor Takashi Taniguchi and Professor Kenji Watanabe from the National Institute for Materials Science [物質・材料研究機構] (JP).

    The study focuses on quasi particles that consist of both matter and light, known as exciton-polaritons—the product of strong couplings between excited electrons in solids and light particles (photons). They form when electrons are stimulated by laser light into a higher energy state. After a short time in the order of one trillionth of a second, the electrons return to their ground state by re-emitting light particles.

    When these particles are trapped between two mirrors, they can in turn excite new electrons—a cycle that repeats until the light particle escapes the trap. The light-matter hybrid particles that are created in this process are called exciton-polaritons. They combine interesting properties of electrons and photons and behave in a similar way to certain physical particles called bosons. “Devices that can control these novel light-matter states hold the promise of a technological leap in comparison with current electronic circuits,” said lead author Anton-Solanas, a postdoctoral researcher in the Quantum Materials Group at the University of Oldenburg’s Institute of Physics. Such optoelectronic circuits, which operate using light instead of electric current, could be better and faster at processing information than today’s processors.

    In the new study, the team led by Anton-Solanas and Schneider looked at exciton-polaritons in ultrathin crystals consisting of a single layer of atoms. These two-dimensional crystals often have unusual physical properties. For example, the semiconductor material used here, molybdenum diselenide, is highly reactive to light.

    The researchers constructed sheets of molybdenum diselenide less than one nanometre (a billionth of a meter) thick and sandwiched the two-dimensional crystal between two layers of other materials that reflect light particles like mirrors do. “This structure acts like a cage for light,” Anton-Solanas explained. Physicists call it a “microcavity.”

    Anton-Solanas and his colleagues cooled their setup to a few degrees above absolute zero and stimulated the formation of exciton-polaritons using short pulses of laser light. Above a certain intensity they observed a sudden increase in the light emissions from their sample. This, together with other evidence, allowed them to conclude that they had succeeded in creating a Bose-Einstein Condensate out of exciton-polaritons.

    “In theory, this phenomenon could be used to construct coherent light sources based on just a single layer of atoms,” said Anton-Solanas. “This would mean we had created the smallest possible solid-state laser.” The researchers are confident that with other materials the effect could also be produced at room temperature, so that in the long term it would also be suitable for practical applications. The team’s first experiments heading in this direction have already been successful.

    See the full article here .

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    Please help promote STEM in your local schools.

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  • richardmitnick 8:23 pm on May 3, 2021 Permalink | Reply
    Tags: "1D model helps clarify implosion performance at NIF", , , , , Laser Technology,   

    From National Ignition Facility at DOE’s Lawrence Livermore National Laboratory (US) : “1D model helps clarify implosion performance at NIF” 

    From National Ignition Facility at DOE’s Lawrence Livermore National Laboratory (US)

    Lawrence Livermore National Laboratory(US)/National Ignition Facility

    4.30.21

    Michael Padilla
    padilla37@llnl.gov
    925-341-8692

    1
    These images depict various laser profiles used in the inertial confinement fusion research and provides the experimental set-up for the VISAR-based shock velocity measurement and representative streaked data.

    In inertial confinement fusion (ICF) experiments at the National Ignition Facility (NIF), a spherical shell of deuterium-tritium fuel is imploded in an attempt to reach the conditions needed for fusion, self-heating and eventual ignition. Since theory and simulations indicate that ignition efficacy in one-dimension (1D) improves with increasing imploded fuel convergence ratio, it is useful to understand the sensitivity of the scale-invariant fuel convergence on all measurable or inferable 1D parameters.

    In a paper featured in Physics of Plasmas , researchers have developed a compression scaling model that is benchmarked to 1D implosion simulations spanning a variety of relevant implosion designs. This model is used to compare compressibility trends across all existing indirect-drive layered implosion data for three ablators.

    “The best level of compression of the various designs of indirect-drive implosions at NIF that have used plastic polymer and beryllium shells follow the expectations of a simple physics model,” said Otto “Nino” Landen from Lawrence Livermore National Laboratory (LLNL) who served as lead author. “This has allowed us to rule out certain previously hypothesized effects such as hot electron preheat.”

    A major exception is the high-density carbon shells that have so far exhibited a remarkably constant lower level of compression, independent of the laser drive conditions, he said.

    “Achieving ignition is fundamentally recognized as a trade-off between more energy coupled to the capsule requiring more efficient hohlraums or a larger laser, and improving the level of capsule compression,” Landen said. “So, understanding what the NIF implosion database has told us so far about compression trends as we varied laser and capsule parameters seemed important as a first step to motivating further research in improving compression without necessarily resorting to a higher laser energy demand.”

    This trending work is part of improving understanding of and optimizing ICF implosion performance on the quest for robust ignition that also could be applied to the direct-drive ICF database.

    The work was conducted by first validating a simple analytic model for the level of capsule compression as a function of various laser and capsule parameters by comparing to 1D simulations.

    Researchers then compared the compression model scaling to all NIF cryogenic implosions shot to date using a combination of existing optical, X-ray and nuclear data, so essentially a physics-grounded empirical approach. This also required developing approximate analytic models for relating the expected compressibility of the implosion to the X-ray driven pressure profile applied to it in the hohlraum as measured by the NIF VISAR system.

    Landen said that since high-density carbon shells are currently giving the best neutron yields despite the reduced compression trends presented in this paper, researchers have increased focus on testing physics-based hypotheses such as hydrodynamic instabilities leading to mixing between the shell and DT, and as yet untested schemes for improving compression in high-density carbon shell implosions.

    The work was conducted by researchers from LLNL, University of Rochester Laboratory for Laser Energetics(LLE) and Los Alamos National Laboratory. Co-authors include: John Lindl, Steve Haan, Daniel Casey, Peter Celliers, David Fittinghoff, Narek Gharibyan, Gary Grim, Ed Hartouni, Omar Hurricane, Brian MacGowan, Stephan MacLaren, Marius Millot, Jose Milovich, Prav Patel, Paul Springer and John Edwards from LLNL; Kevin. Meaney, Harry Robey and Petr Volegov from LANL; and Valeri Goncharov from LLE.

    See the full article here .


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    The National Ignition Facility, is a large laser-based inertial confinement fusion (ICF) research device, located at the DOE’s Lawrence Livermore National Laboratory in Livermore, California. NIF uses lasers to heat and compress a small amount of hydrogen fuel with the goal of inducing nuclear fusion reactions. NIF’s mission is to achieve fusion ignition with high energy gain, and to support nuclear weapon maintenance and design by studying the behavior of matter under the conditions found within nuclear weapons. NIF is the largest and most energetic ICF device built to date, and the largest laser in the world.

    Construction on the NIF began in 1997 but management problems and technical delays slowed progress into the early 2000s. Progress after 2000 was smoother, but compared to initial estimates, NIF was completed five years behind schedule and was almost four times more expensive than originally budgeted. Construction was certified complete on 31 March 2009 by the U.S. Department of Energy, and a dedication ceremony took place on 29 May 2009. The first large-scale laser target experiments were performed in June 2009 and the first “integrated ignition experiments” (which tested the laser’s power) were declared completed in October 2010.

    Bringing the system to its full potential was a lengthy process that was carried out from 2009 to 2012. During this period a number of experiments were worked into the process under the National Ignition Campaign, with the goal of reaching ignition just after the laser reached full power, some time in the second half of 2012. The Campaign officially ended in September 2012, at about 1⁄10 the conditions needed for ignition. Experiments since then have pushed this closer to 1⁄3, but considerable theoretical and practical work is required if the system is ever to reach ignition. Since 2012, NIF has been used primarily for materials science and weapons research.

    [caption id="attachment_69836" align="alignnone" width="400"] National Igniton Facility- NIF at LLNL

    The preamplifiers of the National Ignition Facility are the first step in increasing the energy of laser beams as they make their way toward the target chamber

    Lawrence Livermore National Laboratory (LLNL) is an American federal research facility in Livermore, California, United States, founded by the University of California, Berkeley in 1952. A Federally Funded Research and Development Center (FFRDC), it is primarily funded by the U.S. Department of Energy (DOE) and managed and operated by Lawrence Livermore National Security, LLC (LLNS), a partnership of the University of California, Bechtel, BWX Technologies, AECOM, and Battelle Memorial Institute in affiliation with the Texas A&M University System. In 2012, the laboratory had the synthetic chemical element livermorium named after it.

    LLNL is self-described as “a premier research and development institution for science and technology applied to national security.” Its principal responsibility is ensuring the safety, security and reliability of the nation’s nuclear weapons through the application of advanced science, engineering and technology. The Laboratory also applies its special expertise and multidisciplinary capabilities to preventing the proliferation and use of weapons of mass destruction, bolstering homeland security and solving other nationally important problems, including energy and environmental security, basic science and economic competitiveness.

    Operated by Lawrence Livermore National Security, LLC, for the Department of Energy’s National Nuclear Security Administration

    NNSA

     
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