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  • richardmitnick 1:49 pm on July 10, 2019 Permalink | Reply
    Tags: , , Atomic force microscopy, Computational materials science, Coupled cluster theory, DFT-density functional theory, Kelvin probe force microscopy, , Molecular beam epitaxy, ,   

    From Argonne Leadership Computing Facility: “Predicting material properties with quantum Monte Carlo” 

    Argonne Lab
    News from Argonne National Laboratory

    From Argonne Leadership Computing Facility

    July 9, 2019
    Nils Heinonen

    1
    For one of their efforts, the team used diffusion Monte Carlo to compute how doping affects the energetics of nickel oxide. Their simulations revealed the spin density difference between bulks of potassium-doped nickel oxide and pure nickel oxide, showing the effects of substituting a potassium atom (center atom) for a nickel atom on the spin density of the bulk. Credit: Anouar Benali, Olle Heinonen, Joseph A. Insley, and Hyeondeok Shin, Argonne National Laboratory.

    Recent advances in quantum Monte Carlo (QMC) methods have the potential to revolutionize computational materials science, a discipline traditionally driven by density functional theory (DFT). While DFT—an approach that uses quantum-mechanical modeling to examine the electronic structure of complex systems—provides convenience to its practitioners and has unquestionably yielded a great many successes throughout the decades since its formulation, it is not without shortcomings, which have placed a ceiling on the possibilities of materials discovery. QMC is poised to break this ceiling.

    The key challenge is to solve the quantum many-body problem accurately and reliably enough for a given material. QMC solves these problems via stochastic sampling—that is, by using random numbers to sample all possible solutions. The use of stochastic methods allows the full many-body problem to be treated while circumventing large approximations. Compared to traditional methods, they offer extraordinary potential accuracy, strong suitability for high-performance computing, and—with few known sources of systematic error—transparency. For example, QMC satisfies a mathematical principle that allows it to set a bound for a given system’s ground state energy (the lowest-energy, most stable state).

    QMC’s accurate treatment of quantum mechanics is very computationally demanding, necessitating the use of leadership-class computational resources and thus limiting its application. Access to the computing systems at the Argonne Leadership Computing Facility (ALCF) and the Oak Ridge Leadership Computing Facility (OLCF)—U.S. Department of Energy (DOE) Office of Science User Facilities—has enabled a team of researchers led by Paul Kent of Oak Ridge National Laboratory (ORNL) to meet the steep demands posed by QMC. Supported by DOE’s Innovative and Novel Computational Impact on Theory and Experiment (INCITE) program, the team’s goal is to simulate promising materials that elude DFT’s investigative and predictive powers.

    To conduct their work, the researchers employ QMCPACK, an open-source QMC code developed by the team. It is written specifically for high-performance computers and runs on all the DOE machines. It has been run at the ALCF since 2011.

    Functional materials

    The team’s efforts are focused on studies of materials combining transition metal elements with oxygen. Many of these transition metal oxides are functional materials that have striking and useful properties. Small perturbations in the make-up or structure of these materials can cause them to switch from metallic to insulating, and greatly change their magnetic properties and ability to host and transport other atoms. Such attributes make the materials useful for technological applications while posing fundamental scientific questions about how these properties arise.

    The computational challenge has been to simulate the materials with sufficient accuracy: the materials’ properties are sensitive to small changes due to complex quantum mechanical interactions, which make them very difficult to model.

    The computational performance and large memory of the ALCF’s Theta system have been particularly helpful to the team. Theta’s storage capacity has enabled studies of material changes caused by small perturbations such as additional elements or vacancies. Over three years the team developed a new technique to more efficiently store the quantum mechanical wavefunctions used by QMC, greatly increasing the range of materials that could be run on Theta.

    ANL ALCF Theta Cray XC40 supercomputer

    Experimental Validation

    Kent noted that experimental validation is a key component of the INCITE project. “The team is leveraging facilities located at Argonne and Oak Ridge National Laboratories to grow high-quality thin films of transition-metal oxides,” he said, including vanadium oxide (VO2) and variants of nickel oxide (NiO) that have been modified with other compounds.

    For VO2, the team combined atomic force microscopy, Kelvin probe force microscopy, and time-of-flight secondary ion mass spectroscopy on VO2 grown at ORNL’s Center for Nanophase Materials Science (CNMS) to demonstrate how oxygen vacancies suppress the transition from metallic to insulating VO2. A combination of QMC, dynamical mean field theory, and DFT modeling was deployed to identify the mechanism by which this phenomenon occurs: oxygen vacancies leave positively charged holes that are localized around the vacancy site and end up distorting the structure of certain vanadium orbitals.

    For NiO, the challenge was to understand how a small quantity of dopant atoms, in this case potassium, modifies the structure and optical properties. Molecular beam epitaxy at Argonne’s Materials Science Division was used to create high quality films that were then probed via techniques such as x-ray scattering and x-ray absorption spectroscopy at Argonne’s Advanced Photon Source (APS) [below] for direct comparison with computational results. These experimental results were subsequently compared against computational models employing QMC and DFT. The APS and CNMS are DOE Office of Science User Facilities.

    So far the team has been able to compute, understand, and experimentally validate how the band gap of materials containing a single transition metal element varies with composition. Band gaps determine a material’s usefulness as a semiconductor—a substance that can alternately conduct or cease the flow of electricity (which is important for building electronic sensors or devices). The next steps of the study will be to tackle more complex materials, with additional elements and more subtle magnetic properties. While more challenging, these materials could lead to greater discoveries.

    New chemistry applications

    Many of the features that make QMC attractive for materials also make it attractive for chemistry applications. An outside colleague—quantum chemist Kieron Burke of the University of California, Irvine—provided the impetus for a paper published in Journal of Chemical Theory and Computation. Burke approached the team’s collaborators with a problem he had encountered while trying to formulate a new method for DFT. Moving forward with his attempt required benchmarks against which to test his method’s accuracy. As QMC was the only means by which sufficiently precise benchmarks could be obtained, the team produced a series of calculations for him.

    The reputed gold standard for many-body system numerical techniques in quantum chemistry is known as coupled cluster theory. While it is extremely accurate for many molecules, some are so strongly correlated quantum-mechanically that they can be thought of as existing in a superposition of quantum states. The conventional coupled cluster method cannot handle something so complicated. Co-principal investigator Anouar Benali, a computational scientist at the ALCF and Argonne’s Computational Sciences Division, spent some three years collaborating on efforts to expand QMC’s capability so as to include both low-cost and highly efficient support for these states that will in future also be needed for materials problems. Performing analysis on the system for which Burke needed benchmarks required this superposition support; he verified the results of his newly developed DFT approach against the calculations generated with Benali’s QMC expansion. They were in close agreement with each other, but not with the results conventional coupled cluster had generated—which, for one particular compound, contained significant errors.

    “This collaboration and its results have therefore identified a potential new area of research for the team and QMC,” Kent said. “That is, tackling challenging quantum chemical problems.”

    The research was supported by DOE’s Office of Science. ALCF and OLCF computing time and resources were allocated through the INCITE program.

    See the full article here .

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    Argonne National Laboratory seeks solutions to pressing national problems in science and technology. The nation’s first national laboratory, Argonne conducts leading-edge basic and applied scientific research in virtually every scientific discipline. Argonne researchers work closely with researchers from hundreds of companies, universities, and federal, state and municipal agencies to help them solve their specific problems, advance America’s scientific leadership and prepare the nation for a better future. With employees from more than 60 nations, Argonne is managed by UChicago Argonne, LLC for the U.S. Department of Energy’s Office of Science. For more visit http://www.anl.gov.

    About ALCF
    The Argonne Leadership Computing Facility’s (ALCF) mission is to accelerate major scientific discoveries and engineering breakthroughs for humanity by designing and providing world-leading computing facilities in partnership with the computational science community.

    We help researchers solve some of the world’s largest and most complex problems with our unique combination of supercomputing resources and expertise.

    ALCF projects cover many scientific disciplines, ranging from chemistry and biology to physics and materials science. Examples include modeling and simulation efforts to:

    Discover new materials for batteries
    Predict the impacts of global climate change
    Unravel the origins of the universe
    Develop renewable energy technologies

    Argonne is managed by UChicago Argonne, LLC for the U.S. Department of Energy’s Office of Science

    Argonne Lab Campus


     
  • richardmitnick 12:05 pm on August 10, 2018 Permalink | Reply
    Tags: , , , Lining Up the Surprising Behaviors of a Superconductor with One of the World's Strongest Magnets, , Molecular beam epitaxy, National High Magnetic Field Laboratory, Pulsed Field Facility at Los Alamos National Laboratory,   

    From Brookhaven National Lab: “Lining Up the Surprising Behaviors of a Superconductor with One of the World’s Strongest Magnets” 

    From Brookhaven National Lab

    August 8, 2018

    atantillo@bnl.gov
    Ariana Tantillo
    (631) 344-2347

    Peter Genzer,
    genzer@bnl.gov
    (631) 344-3174

    Scientists have discovered that the electrical resistance of a copper-oxide compound depends on the magnetic field in a very unusual way—a finding that could help direct the search for materials that can perfectly conduct electricity at room temperature.

    1
    (Clockwise from back left) Brookhaven Lab physicists Ivan Bozovic, Anthony Bollinger, and Jie Wu, and postdoctoral researcher Xi He used the molecular beam epitaxy system seen above to synthesize perfect single-crystal thin films made of lanthanum, strontium, oxygen, and copper (LSCO). They brought these superconducting films to the National High Magnetic Field Laboratory to see how the electrical resistance of LSCO in its “strange” metallic state changes under extremely strong magnetic fields.

    What happens when really powerful magnets—capable of producing magnetic fields nearly two million times stronger than Earth’s—are applied to materials that have a “super” ability to conduct electricity when chilled by liquid nitrogen? A team of scientists set out to answer this question in one such superconductor made of the elements lanthanum, strontium, copper, and oxygen (LSCO). They discovered that the electrical resistance of this copper-oxide compound, or cuprate, changes in an unusual way when very high magnetic fields suppress its superconductivity at low temperatures.

    “The most pressing problem in condensed matter physics is understanding the mechanism of superconductivity in cuprates because at ambient pressure they become superconducting at the highest temperature of any currently known material,” said physicist Ivan Bozovic, who leads the Oxide Molecular Beam Epitaxy Group at the U.S. Department of Energy’s (DOE) Brookhaven National Laboratory and who is a coauthor of the Aug. 3 Science paper reporting the discovery. “This new result—that the electrical resistivity of LSCO scales linearly with magnetic field strength at low temperatures—provides further evidence that high-temperature superconductors do not behave like ordinary metals or superconductors. Once we can come up with a theory to explain their unusual behavior, we will know whether and where to search for superconductors that can carry large amounts of electrical current at higher temperatures, and perhaps even at room temperature.”

    Cuprates such as LSCO are normally insulators. Only when they are cooled to some hundred degrees below zero and the concentrations of their chemical composition are modified (a process called doping) to a make them metallic can their mobile electrons pair up to form a “superfluid” that flows without resistance. Scientists hope that understanding how cuprates achieve this amazing feat will enable them to develop room-temperature superconductors, which would make energy generation and delivery significantly more efficient and less expensive.

    In 2016, Bozovic’s group reported that LSCO’s superconducting state is nothing like the one explained by the generally accepted theory of classical superconductivity; it depends on the number of electron pairs in a given volume rather than the strength of the electron pairing interaction. In a follow-up experiment published the following year, they obtained another puzzling result: when LSCO is in its non-superconducting (normal, or “metallic”) state, its electrons do not behave as a liquid, as would be expected from the standard understanding of metals.

    “The condensed matter physics community has been divided about this most basic question: do the behaviors of cuprates fall within existing theories for superconductors and metals, or are there profoundly different physical principles involved?” said Bozovic.

    Continuing this comprehensive multipart study that began in 2005, Bozovic’s group and collaborators have now found additional evidence to support the latter idea that the existing theories are incomplete. In other words, it is possible that these theories do not encompass every known material. Maybe there are two different types of metals and superconductors, for example.

    “This study points to another property of the strange metallic state in the cuprates that is not typical of metals: linear magnetoresistance at very high magnetic fields,” said Bozovic. “At low temperatures where the superconducting state is suppressed, the electrical resistivity of LSCO scales linearly (in a straight line) with the magnetic field; in metals, this relationship is quadratic (forms a parabola).”

    2
    This composite image offers a glimpse inside the custom-designed molecular beam epitaxy system that the Brookhaven physicists use to create single-crystal thin films for studying the properties of superconducting cuprates.

    In order to study magneto resistance, Bozovic and group members Anthony Bollinger, Xi He, and Jie Wu first had to create flawless single-crystal thin films of LSCO near its optimal doping level. They used a technique called molecular beam epitaxy, in which separate beams containing atoms of the different chemical elements are fired onto a heated single-crystal substrate. When the atoms land on the substrate surface, they condense and slowly grow into ultra-thin layers, building a single atomic layer at a time. The growth of the crystal occurs in highly controlled conditions of ultra-high vacuum to ensure that the samples do not get contaminated.

    “Brookhaven Lab’s key contribution to this study is this material synthesis platform,” said Bozovic. “It allows us to tailor the chemical composition of the films for different studies and provides the foundation for us to observe the true properties of superconducting materials, as opposed to properties induced by sample defects or impurities.”

    The scientists then patterned the thin films onto strips containing voltage leads so that the amount of electrical current flowing through LSCO under an applied magnetic field could be measured.

    They conducted initial magneto resistivity measurements with two 9 Tesla magnets at Brookhaven Lab—for reference, the strength of the magnets used in today’s magnetic resonance imaging (MRI) machines are typically up to 3 Tesla. Then, they brought their best samples (those with the best structural and transport qualities) to the Pulsed Field Facility. Located at DOE’s Los Alamos National Laboratory, this international user facility is part of the National High Magnetic Field Laboratory, which houses some of the strongest magnets in the world. Scientists at the Pulsed Field Facility placed the samples in an 80 Tesla pulsed magnet, powered by quick pulses, or shots, of electrical current. The magnet produces such large magnetic fields that it cannot be energized for more than a very short period of time (microseconds to a fraction of a second) without destroying itself.

    “This large magnet, which is the size of a room and draws the electricity of a small city, is the only such installation on this continent,” said Bozovic. “We only get access to it once a year if we are lucky, so we chose our best samples to study.”

    In October, the scientists will get access to a stronger (90 Tesla) magnet, which they will use to collect additional magneto resistance data to see if the linear relationship still holds.

    3
    An example of a typical device that the scientists use to measure electrical resistivity as a function of temperature and magnetic field. The scientists grew the film via atomic layer-by-layer molecular beam epitaxy, patterned it into a device, and wire bonded it to a chip carrier.

    “While I do not expect to see something different, this higher field strength will allow us to expand the range of doping levels at which we can suppress superconductivity,” said Bozovic. “Collecting more data over a broader range of chemical compositions will help theorists formulate the ultimate theory of high-temperature superconductivity in cuprates.”

    In the next year, Bozovic and the other physicists will collaborate with theorists to interpret the experimental data.

    “It appears that the strongly correlated motion of electrons is behind the linear relationship we observed,” said Bozovic. “There are various ideas of how to explain this behavior, but at this point, I would not single out any of them.”

    See the full article here .


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    One of ten national laboratories overseen and primarily funded by the Office of Science of the U.S. Department of Energy (DOE), Brookhaven National Laboratory conducts research in the physical, biomedical, and environmental sciences, as well as in energy technologies and national security. Brookhaven Lab also builds and operates major scientific facilities available to university, industry and government researchers. The Laboratory’s almost 3,000 scientists, engineers, and support staff are joined each year by more than 5,000 visiting researchers from around the world. Brookhaven is operated and managed for DOE’s Office of Science by Brookhaven Science Associates, a limited-liability company founded by Stony Brook University, the largest academic user of Laboratory facilities, and Battelle, a nonprofit, applied science and technology organization.
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  • richardmitnick 2:11 pm on December 11, 2017 Permalink | Reply
    Tags: , , Crystal structures, Molecular beam epitaxy, , ,   

    From Notre Dame: “Thirty years of molecular beam epitaxy stimulates international collaborations” 

    Notre Dame bloc

    Notre Dame University

    December 08, 2017
    Tammi Freehling

    1
    Margaret Dobrowolska and Jacek Furdyna in the MBE lab at Notre Dame.

    For nearly thirty years, Professor Jacek Furdyna’s Molecular Beam Epitaxy (MBE) lab at Notre Dame has been providing crystals and materials to students and scientists across the world. In continuous operation since its beginning in 1987, more than 10,000 crystals have been grown in the lab, most in the form of “designer-materials” such as new crystal phases, quantum wells, quantum dots, and other forms that do not occur in nature.

    Growing such crystal structures requires specific combinations of atoms from different elements. Molecular Beam Epitaxy accomplishes this by assembling these atoms into a single crystal on a substrate, atomic layer by atomic layer. Not surprisingly, this must be done under ultra-high vacuum conditions, ensuring ultra-high purity of the resulting material, with no unwanted foreign atoms present.

    “The process of MBE allows us to create materials by assembling the atoms one-by-one, ‘on demand’. Thus we are able to form entirely new crystal phases and, more importantly, to obtain materials with entirely new atomic configurations (such as quantum wells, superlattices, quantum wires, and quantum dots) that perform specific optical, electrical, or magnetic functions that can be applied in solid state devices,” said Margaret Dobrowolska, the Rev. John Cardinal O’Hara, C.S.C. Professor of Physics and associate dean for undergraduate studies, College of Science, who works with Furdyna in the MBE lab (and happens to be his wife). The resulting materials are highly precise films that are widely used in the manufacture of semiconductor devices, such as semiconductor transistors of various forms, light emitting diodes (LEDs), semiconductor lasers, and a myriad other components for modern-day electronics.

    Molecular Beam Epitaxy was invented in the late 1960s at Bell Telephone Laboratories by J. R. Arthur and Alfred Y. Cho. In 1987, Furdyna came to Notre Dame from Purdue and set up the MBE lab in Nieuwland Science Hall. His research interests involve the preparation of new semiconducting compounds and the investigation of their physical properties. Most recently, this activity has focused on three semiconducting systems: quantum well structures for use in blue and blue-green light emitters, including semiconductor lasers; magnetic semiconductors (which combine “traditional” semiconductor phenomena with new magnetic properties, including ferromagnetism); and semiconductor nanostructures, such as self-assembled quantum dots, quantum wires, and their arrays. These systems are investigated by structural, electrical, magnetic, and optical techniques, which provide basic understanding of the electronic and magnetic structures of the new semiconducting materials, as well as the knowledge necessary for constructing electronic and optical devices based on the above materials. One should note here that, because the structures achieved by MBE are controlled at atomic-scale precision, this method provides one of the most effective approaches to the new wave of technology referred to as nanotechnology.

    In addition to the spectroscopic studies carried out at Notre Dame, Furdyna together with his colleagues Dobrowolska and Xinyu Liu, associate research professor of physics, are involved in an extensive program of collaborations with other institutions in the area of structural studies, magnetic measurements, and neutron scattering on the semiconductor systems described above. Materials designed and fabricated in the MBE lab led to collaborations with scientists in more than 100 institutions outside of Notre Dame, including some 35 in foreign countries, resulting in significant worldwide visibility for Notre Dame.

    “One of the most gratifying things about having the MBE lab here at Notre Dame is that it stimulates such extensive international collaborations,” Furdyna said. “As an illustration, in just the past five years alone we’ve had about 10 long-term visiting scientists, including graduate students and postdocs from Ireland, South Korea, Venezuela, Brazil, Poland, and Russia. Apart from getting a great deal of work done, they’ve seriously contributed to broadening our horizons.”

    Furdyna further commented: “More than 40 Notre Dame graduate students carried out their Ph.D. research on materials provided by the MBE lab. Since the MBE lab opened in 1987, the cumulative number of refereed publications by our group is about 700, and the number of citations of these papers in the scientific literature is over 14,000. More than 120 graduate students in institutions other than Notre Dame carried out their Ph.D. research on materials provided by our MBE lab. This includes 90 Ph.D. students in U.S. universities and 30 students in universities abroad. In the area of new semiconductor materials, and particularly in systems involving magnetic semiconductors, our lab has become the ‘go-to place’ in research involving these research fields.”

    See the full article here .

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    The University of Notre Dame du Lac (or simply Notre Dame /ˌnoʊtərˈdeɪm/ NOH-tər-DAYM) is a Catholic research university located near South Bend, Indiana, in the United States. In French, Notre Dame du Lac means “Our Lady of the Lake” and refers to the university’s patron saint, the Virgin Mary.

    The school was founded by Father Edward Sorin, CSC, who was also its first president. Today, many Holy Cross priests continue to work for the university, including as its president. It was established as an all-male institution on November 26, 1842, on land donated by the Bishop of Vincennes. The university first enrolled women undergraduates in 1972. As of 2013 about 48 percent of the student body was female.[6] Notre Dame’s Catholic character is reflected in its explicit commitment to the Catholic faith, numerous ministries funded by the school, and the architecture around campus. The university is consistently ranked one of the top universities in the United States and as a major global university.

    The university today is organized into five colleges and one professional school, and its graduate program has 15 master’s and 26 doctoral degree programs.[7][8] Over 80% of the university’s 8,000 undergraduates live on campus in one of 29 single-sex residence halls, each of which fields teams for more than a dozen intramural sports, and the university counts approximately 120,000 alumni.[9]

    The university is globally recognized for its Notre Dame School of Architecture, a faculty that teaches (pre-modernist) traditional and classical architecture and urban planning (e.g. following the principles of New Urbanism and New Classical Architecture).[10] It also awards the renowned annual Driehaus Architecture Prize.

     
  • richardmitnick 7:36 pm on June 26, 2017 Permalink | Reply
    Tags: , Electromagnetic radiation [light], Hyperbolic metamaterials (HMMs), Molecular beam epitaxy, Nanoresonators, , , , ,   

    From Notre Dame: “Notre Dame Researchers Open Path to New Generation of Optical Devices” 

    Notre Dame bloc

    Notre Dame University

    COLLEGE of ENGINEERING

    OFFICE of the PROVOST
    College of Engineering

    June 22, 2017
    Nina Welding

    1
    Sub-diffraction Confinement in All-semiconductor Hyperbolic Metamaterial Resonators was co-authored by graduate students Kaijun Feng and Galen Harden and Deborah L. Sivco, engineer-in-residence at MIRTHE+ Photonics Sensing Center, Princeton Univ.

    Cameras, telescopes and microscopes are everyday examples of optical devices that measure and manipulate electromagnetic radiation [light]. Being able to control the light in such devices provides the user with more information through a much better “picture” of what is occurring through the lens. The more information one can glean, the better the next generation of devices can become. Similarly, controlling light on small scales could lead to improved optical sources for applications that span health, homeland security and industry. This is what a team of researchers, led by Anthony Hoffman, assistant professor of electrical engineering and researcher in the University’s Center for Nano Science and Technology (NDnano), has been pursuing. Their findings were recently published in the June 19 issue of ACS Photonics.

    In fact, the team has fabricated and characterized sub-diffraction mid-infrared resonators using all-semiconductor hyperbolic metamaterials (HMMs) that confine light to extremely small volumes — thousands of times smaller than common materials.

    2
    The scanning electron microscope image here shows an array of 0.47 μm wide resonators with a 2.5 μm pitch. No image credit.

    HMMs combine the properties of metals, which are excellent conductors, and dielectrics, which are insulators, to realize artificial optical materials with properties that are very difficult, even impossible, to find naturally. These unusual properties may elucidate the quantum mechanical interactions between light and matter at the nanoscale while giving researchers a powerful tool to control and engineer these light-matter interactions for new optical devices and materials.

    Hoffman’s team engineered these desired properties in the HMMs by growing them via molecular beam epitaxy using III-V semiconductor materials routinely used for high-performance optoelectronic devices, such as lasers and detectors. Layers of Si-doped InGaAs and intrinsic AlInAs were placed on top of one another, with a single layer being 50 nm thick. The total thickness of the HMM was 1μm, about 100 times smaller than the width of a human hair.

    The nanoresonators were produced by Kaijun Feng, graduate student in the Department of Electrical Engineering, using state-of-the-art fabrication equipment in Notre Dame’s Nanofabrication Facility. The devices were then characterized in Hoffman’s laboratory using a variety of spectroscopic techniques.

    “What is particularly exciting about this work,” says Hoffman, “is that we have found a way to squeeze light into small volumes using a mature semiconductor technology. In addition to being able to employ these nanoresonators to generate mid-infrared light, we believe that these new sources could have significant application in the mid-infrared portion of the spectrum, which is used for optical sensing across areas such as medicine, environmental monitoring, industrial process control and defense. We are also excited about the possibility of utilizing these nanoresonators to study interactions between light and matter that previously have not been possible.”

    See the full article here .

    Please help promote STEM in your local schools.

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    Notre Dame Campus

    The University of Notre Dame du Lac (or simply Notre Dame /ˌnoʊtərˈdeɪm/ NOH-tər-DAYM) is a Catholic research university located near South Bend, Indiana, in the United States. In French, Notre Dame du Lac means “Our Lady of the Lake” and refers to the university’s patron saint, the Virgin Mary.

    The school was founded by Father Edward Sorin, CSC, who was also its first president. Today, many Holy Cross priests continue to work for the university, including as its president. It was established as an all-male institution on November 26, 1842, on land donated by the Bishop of Vincennes. The university first enrolled women undergraduates in 1972. As of 2013 about 48 percent of the student body was female.[6] Notre Dame’s Catholic character is reflected in its explicit commitment to the Catholic faith, numerous ministries funded by the school, and the architecture around campus. The university is consistently ranked one of the top universities in the United States and as a major global university.

    The university today is organized into five colleges and one professional school, and its graduate program has 15 master’s and 26 doctoral degree programs.[7][8] Over 80% of the university’s 8,000 undergraduates live on campus in one of 29 single-sex residence halls, each of which fields teams for more than a dozen intramural sports, and the university counts approximately 120,000 alumni.[9]

    The university is globally recognized for its Notre Dame School of Architecture, a faculty that teaches (pre-modernist) traditional and classical architecture and urban planning (e.g. following the principles of New Urbanism and New Classical Architecture).[10] It also awards the renowned annual Driehaus Architecture Prize.

     
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