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  • richardmitnick 10:34 am on February 14, 2020 Permalink | Reply
    Tags: , , BNL, Light Sources Form Data Solution Task Force", ,   

    From Brookhaven National Lab: “Light Sources Form Data Solution Task Force” 

    From Brookhaven National Lab

    February 12, 2020
    Stephanie Kossman
    skossman@bnl.gov

    New collaboration between scientists at the five U.S. Department of Energy light source facilities will develop flexible software to easily process big data.

    BNL NSLS-II

    LBNL ALS

    ANL Advanced Photon Source

    SLAC SSRL Campus

    SLAC LCLS

    Above are the five DOE light sources: Brookhaven National Laboratory’s National Synchrotron Light Source II (NSLS-II), Lawrence Berkeley National Laboratory’s Advanced Light Source (ALS), Argonne National Laboratory’s Advanced Photon Source (APS), and SLAC National Accelerator Laboratory’s Stanford Synchrotron Radiation Lightsource (SSRL) and Linac Coherent Light Source (LCLS).

    Light source facilities are tackling some of today’s biggest scientific challenges, from designing new quantum materials to revealing protein structures. But as these facilities continue to become more technologically advanced, processing the wealth of data they produce has become a challenge of its own. By 2028, the five U.S. Department of Energy (DOE) Office of Science light sources, will produce data at the exabyte scale, or on the order of billions of gigabytes, each year. Now, scientists have come together to develop synergistic software to solve that challenge.

    With funding from DOE for a two-year pilot program, scientists from the five light sources have formed a Data Solution Task Force that will demonstrate, build, and implement software, cyberinfrastructure, and algorithms that address universal needs between all five facilities. These needs range from real-time data analysis capabilities to data storage and archival resources.

    “It is exciting to see the progress that is being made by all the light sources working together to produce solutions that will be deployed across the whole DOE complex,” said Stuart Campbell, leader of the data acquisition, management and analysis group at the National Synchrotron Light Source II (NSLS-II), a DOE Office of Science user facility at DOE’s Brookhaven National Laboratory.

    In addition, the new software will be designed to facilitate multimodal research—studies that combine data collected from multiple experimental stations, called beamlines. Typically, each beamline at a light source uses custom-built data acquisition software that is incompatible with another beamline’s, making it difficult for scientists to collect and compare data from multiple experimental stations. The task force aims to develop flexible software that can be deployed at multiple beamlines across all five facilities, expanding the possibilities for scientific collaboration.

    2
    Members of the task force met at NSLS-II for a project kickoff meeting in August of 2019.

    To develop the new software, the task force will start by building up existing solutions that can already be found at the five light sources. Two of the key components are Bluesky, an open source software that was created at NSLS-II, and Xi-CAM, which was developed at the Advanced Light Source (ALS) and the Center for Advanced Mathematics for Energy Research Applications—both at DOE’s Lawrence Berkeley National Laboratory. Together, Bluesky and Xi-Cam will provide capabilities like live visualization and interactivity, data processing tools, and the ability to export data in real time into nearly any file format.

    Each of the five light sources in the task force is bringing unique tools and skillsets to help develop a more robust and scalable solution to extract scientific knowledge from data for the nation’s light sources.

    “There is tremendous enthusiasm at the light sources for solving the data challenge,” said Alexander Hexemer, senior scientist and computing program lead at ALS. “We strongly believe this will be the path forward for light sources to work together in the future.”

    With the task force in its early stages, researchers have begun running test experiments on beamlines at NSLS-II and installing Bluesky and Xi-CAM at the Advanced Photon Source, a DOE Office of Science user facility at DOE’s Argonne National Laboratory.

    By the end of the two-year pilot project, “we plan to deliver a set of tools that will provide an end-to-end software solution for the targeted scientific areas that can be deployed and used on different beamlines across all the DOE light sources,” Campbell said.

    Alongside the task force pilot, the five light sources are working with DOE to develop data systems solutions that will scale to the unprecedented data rates that will be produced in the near future, using the new generation of “exascale” computers being built by DOE.

    See the full article here .


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

    Please help promote STEM in your local schools.

    Stem Education Coalition

    BNL Campus

    Brookhaven campus

    BNL Center for Functional Nanomaterials

    BNL NSLS-II


    BNL NSLS II

    BNL RHIC Campus

    BNL/RHIC Star Detector

    BNL Phenix Detector

    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.

     
  • richardmitnick 12:40 pm on February 7, 2020 Permalink | Reply
    Tags: "Making High-Temperature Superconductivity Disappear to Understand Its Origin", (SI-STM)-spectroscopic imaging–scanning tunneling microscopy, , , BNL, , , , , OASIS- a new on-site experimental machine for growing and characterizing oxide thin films., ,   

    From Brookhaven National Lab: “Making High-Temperature Superconductivity Disappear to Understand Its Origin” 

    From Brookhaven National Lab

    February 3, 2020
    Ariana Manglaviti
    amanglaviti@bnl.gov
    (631) 344-2347

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

    Scientists have collected evidence suggesting that a purely electronic mechanism causes copper-oxygen compounds to conduct electricity without resistance at temperatures well above absolute zero.

    1
    Brookhaven Lab physicists (from left to right) Genda Gu, Tonica Valla, and Ilya Drozdov at OASIS, a new on-site experimental machine for growing and characterizing oxide thin films, such as those of a class of high-temperature superconductors (HTS) known as the cuprates. Compared to conventional superconductors, HTS become able to conduct electricity without resistance at much warmer temperatures. The team used the unique capabilities at OASIS to make superconductivity in a cuprate sample disappear and then reappear in order to understand the origin of the phenomenon.

    When there are several processes going on at once, establishing cause-and-effect relationships is difficult. This scenario holds true for a class of high-temperature superconductors known as the cuprates. Discovered nearly 35 years ago, these copper-oxygen compounds can conduct electricity without resistance under certain conditions. They must be chemically modified (“doped”) with additional atoms that introduce electrons or holes (electron vacancies) into the copper-oxide layers and cooled to temperatures below 100 Kelvin (−280 degrees Fahrenheit)—significantly warmer temperatures than those needed for conventional superconductors. But exactly how electrons overcome their mutual repulsion and pair up to flow freely in these materials remains one of the biggest questions in condensed matter physics. High-temperature superconductivity (HTS) is among many phenomena occurring due to strong interactions between electrons, making it difficult to determine where it comes from.

    That’s why physicists at the U.S. Department of Energy’s (DOE) Brookhaven National Laboratory studying a well-known cuprate containing layers made of bismuth oxide, strontium oxide, calcium, and copper oxide (BSCCO) decided to focus on the less complicated “overdoped” side, doping the material so much so that superconductivity eventually disappears. As they reported in a paper published on Jan. 29 in Nature Communications, this approach enabled them to identify that purely electronic interactions likely lead to HTS.

    “Superconductivity in cuprates usually coexists with periodic arrangements of electric charge or spin and many other phenomena that can either compete with or aid superconductivity, complicating the picture,” explained first author Tonica Valla, a physicist in the Electron Spectroscopy Group of Brookhaven Lab’s Condensed Matter Physics and Materials Science Division. “But these phenomena weaken or completely vanish with overdoping, leaving nothing but superconductivity. Thus, this is the perfect region to study the origin of superconductivity. Our experiments have uncovered an interaction between electrons in BSCCO that correlates one to one with superconductivity. Superconductivity emerges exactly when this interaction first appears and becomes stronger as the interaction strengthens.”

    Only very recently has it become possible to overdope cuprate samples beyond the point where superconductivity vanishes. Previously, a bulk crystal of the material would be annealed (heated) in high-pressure oxygen gas to increase the concentration of oxygen (the dopant material). The new method—which Valla and other Brookhaven scientists first demonstrated about a year ago at OASIS, a new on-site instrument for sample preparation and characterization—uses ozone instead of oxygen to anneal cleaved samples. Cleaving refers to breaking the crystal in vacuum to create perfectly flat and clean surfaces.

    “The oxidation power of ozone, or its ability to accept electrons, is much stronger than that of molecular oxygen,” explained coauthor Ilya Drozdov, a physicist in the division’s Oxide Molecular Beam Epitaxy (OMBE) Group. “This means we can bring more oxygen into the crystal to create more holes in the copper-oxide planes, where superconductivity occurs. At OASIS, we can overdope surface layers of the material all the way to the nonsuperconducting region and study the resulting electronic excitations.”

    OASIS combines an OMBE system for growing oxide thin films with angle-resolved photoemission spectroscopy (ARPES) and spectroscopic imaging–scanning tunneling microscopy (SI-STM) instruments for studying the electronic structure of these films. Here, materials can be grown and studied using the same connected ultrahigh vacuum system to avoid oxidation and contamination by carbon dioxide, water, and other molecules in the atmosphere. Because ARPES and SI-STM are extremely surface-sensitive techniques, pristine surfaces are critical to obtaining accurate measurements.

    For this study, coauthor Genda Gu, a physicist in the division’s Neutron Scattering Group, grew bulk BSCCO crystals. Drozdov annealed the cleaved crystals in ozone in the OMBE chamber at OASIS to increase the doping until superconductivity was completely lost. The same sample was then annealed in vacuum in order to gradually reduce the doping and increase the transition temperature at which superconductivity emerges. Valla analyzed the electronic structure of BSCCO across this doping-temperature phase diagram through ARPES.

    “ARPES gives you the most direct picture of the electronic structure of any material,” said Valla. “Light excites electrons from a sample, and by measuring their energy and the angle at which they escape, you can recreate the energy and momentum of the electrons while they were still in the crystal.”

    In measuring this energy-versus-momentum relationship, Valla detected a kink (anomaly) in the electronic structure that follows the superconducting transition temperature. The kink becomes more pronounced and shifts to higher energies as this temperature increases and superconductivity gets stronger, but disappears outside of the superconducting state. On the basis of this information, he knew that the interaction creating the electron pairs required for superconductivity could not be electron-phonon coupling, as theorized for conventional superconductors. Under this theory, phonons, or vibrations of atoms in the crystal lattice, serve as an attractive force for otherwise repulsive electrons through the exchange of momentum and energy.

    “Our result allowed us to rule out electron-phonon coupling because atoms in the lattice can vibrate and electrons can interact with those vibrations, regardless of whether the material is superconducting or not,” said Valla. “If phonons were involved, we would expect to see the kink in both the superconducting and normal state, and the kink would not be changing with doping.”

    The team believes that something similar to electron-phonon coupling is going on in this case, but instead of phonons, another excitation gets exchanged between electrons. It appears that electrons are interacting through spin fluctuations, which are related to electrons themselves. Spin fluctuations are changes in electron spin, or the way that electrons point either up or down as tiny magnets.

    Moreover, the scientists found that the energy of the kink is less than that of a characteristic energy at which a sharp peak (resonance) in the spin fluctuation spectrum appears. Their finding suggests that the onset of spin fluctuations (instead of the resonance peak) is responsible for the observed kink and may be the “glue” that binds electrons into the pairs required for HTS.

    Next, the team plans to collect additional evidence showing that spin fluctuations are related to superconductivity by obtaining SI-STM measurements. They will also perform similar experiments on another well-known cuprate, lanthanum strontium copper oxide (LSCO).

    “For the first time, we are seeing something that strongly correlates with superconductivity,” said Valla. “After all these years, we now have a better grasp of what may be causing superconductivity in not only BSCCO but also other cuprates.”

    See the full article here .


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

    Please help promote STEM in your local schools.

    Stem Education Coalition

    BNL Campus

    Brookhaven campus

    BNL Center for Functional Nanomaterials

    BNL NSLS-II


    BNL NSLS II

    BNL RHIC Campus

    BNL/RHIC Star Detector

    BNL Phenix Detector

    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.

     
  • richardmitnick 3:26 pm on January 28, 2020 Permalink | Reply
    Tags: "A New Spin on the Basics", BNL, Computer scientists now are at the precipice of a new computing wave: making the leap from supercomputers and bytes to quantum systems and qubits., Ludwig Boltzmann factor calculates the probability that a system of particles can be found in a specific energy state relative to zero energy is widely used in physics., Quantum computers offer another look at classic physics concepts., The collaboration allows Brookhaven (among others in network) access to IBM’s commercial quantum systems including 20- and 53-qubit systems for experiments., The IBM Q Hub at Oak Ridge National Laboratory   

    From Brookhaven National Lab: “A New Spin on the Basics” 

    From Brookhaven National Lab

    January 27, 2020
    Charity Plata
    cplata@bnl.gov

    Quantum computers offer another look at classic physics concepts.

    1
    During the Computational Science Initiative’s Advisory Board Meeting in July 2019, Raffaele Miceli, who co-authored a study of thermo field quantum algorithms while working as a student at CSI, described his quantum computing research to other summer interns at Brookhaven Lab.

    “Think what we can do if we teach a quantum computer to do statistical mechanics,” posed Michael McGuigan, a computational scientist with the Computational Science Initiative at the U.S. Department of Energy’s Brookhaven National Laboratory.

    At the time, McGuigan was reflecting on Ludwig Boltzmann and how the renowned physicist had to vigorously defend his theories of statistical mechanics. Boltzmann, who proffered his ideas about how atomic properties determine physical properties of matter in the late 19th century, had one extraordinarily huge hurdle: atoms were not even proven to exist at the time. Fatigue and discouragement stemming from his peers not accepting his views on atoms and physics forever haunted Boltzmann.

    2
    Probability associated to the wave function of the universe calculated using Qiskit. The vertical axis denotes the probability of realizing a particular configuration in the simple model of early cosmology, while the other axes indicate scale factor of the universe and magnitude of the inflaton field (from Kocher and McGuigan, 2018).

    Today, Boltzmann’s factor, which calculates the probability that a system of particles can be found in a specific energy state relative to zero energy, is widely used in physics. For example, Boltzmann’s factor is used to perform calculations on the world’s largest supercomputers to study the behavior of atoms, molecules, and the quark “soup” discovered using facilities such as the Relativistic Heavy Ion Collider located at Brookhaven Lab and the Large Hadron Collider at CERN.

    BNL/RHIC

    CERN LHC

    SixTRack CERN LHC particles

    While it took a sea change to show Boltzmann was right, computer scientists now are at the precipice of a new computing wave, making the leap from supercomputers and bytes to quantum systems and quantum bits (or “qubits”). These quantum computers have the potential to unlock some of the most mysterious concepts in physics. And, oddly, these so-called mysteries may seem a bit familiar to many.

    Time and Temperature Brought to You by…

    Although most people are well acquainted with the notions of time and temperature and check on them several times a day, it turns out these basic concepts remain enigmatic in physics.

    Boltzmann’s factor helps model temperature effects that can be used to predict and control atomic behavior and physical properties, and they work great on classical computers. However, on a quantum computer, the quantum logic gates used in the computation (akin to logic gates found in digital circuits) are represented by complex numbers, as opposed to Boltzmann’s factor, which by definition, is real.

    ______________________________________

    This is How We Do It: Boltzmann’s Factor for Finite Temperature Calculations

    These calculations typically are done on classical computers using imaginary time formalism and the Monte Carlo method. The imaginary time method treats time as if it is another space coordinate and wraps it up in circle of size proportional to the reciprocal of the temperature. The Monte Carlo method samples the state of the system randomly and chooses the importance of the state based on Boltzmann’s factor.
    ______________________________________

    This issue offered McGuigan and his student/coauthor Raffaele Miceli an interesting problem to tackle using a quantum computing testbed provided by way of Brookhaven Lab’s access agreement to IBM’s universal quantum computing systems, through the IBM Q Hub at Oak Ridge National Laboratory. The collaboration allows Brookhaven (among others in network) access to IBM’s commercial quantum systems, including 20- and 53-qubit systems for experiments.

    “On a quantum computer, there is another way to simulate finite temperature called thermo field dynamics, which is able to compute quantities that are both time- and temperature-dependent,” McGuigan explained. “In this formalism, you construct a double of the system, called the thermo double, then proceed with the calculation on a quantum computer as the computation can be represented in terms of quantum logic gates with complex numbers.

    “In the end, you can sum the double states and generate an effective Boltzmann’s factor for calculations at finite temperature,” he continued. “There also are certain advantages of the formalism. For example, you can study the effects of finite temperature and how the system evolves in real time as time and temperature are separated using this quantum algorithm. One disadvantage is that it requires twice as many qubits as a zero temperature calculation to handle the double states.”

    Miceli and McGuigan demonstrated how to implement the quantum algorithm for thermo field dynamics for finite temperature on a simple system involving a few particles and found perfect agreement with the classical computation.

    ______________________________________

    This is How We Do It: Running a Thermo Field Quantum Algorithm on a Quantum Computer

    In their work, Miceli and McGuigan applied a unitary transformation to discrete quantum mechanical operators to make new Hamiltonians (that measure kinetic energy in particles) with encoded temperature dependence. These were processed into a Pauli matrix representation and input into IBM’s Qiskit [Quantum Information Science kit] software platform. The quantum simulator then calculated an approximation to the Hamiltonian’s ground state energy via the variational quantum eigensolver (VQE), a hybrid algorithm with both quantum and classical components, which is compared to a classically calculated value for the exact energy.
    ______________________________________

    Their work used resources from both classical and quantum computing. According to McGuigan, they used Qiskit open-source quantum computing software that allowed them to create their algorithm in the cloud. Qiskit then transpiled that code to pulses that communicate with a quantum computer in real time (in this case, an IBM Q device). Optimizers that run classical algorithms further enable the back and forth between the traditional and quantum systems.

    “Our experiment shows quantum systems have an advantage of representing real-time calculations exactly rather than rotating from imaginary time to real time to find a result,” McGuigan explained. “It offers a truer picture of how a system evolves. We can map the problem to a quantum simulation that lets it evolve.”

    Into the Cosmos

    Quantum cosmology is another area where McGuigan anticipates that new quantum computing options will have profound impact. Despite the multitude of advances in understanding the universe made possible by modern supercomputers, some physical systems remain beyond their reach. The mathematical complexity, which usually includes accounting for full quantum gravity theory, is simply too great to obtain exact solutions. However, a true quantum computer, complete with the ability to exploit entanglement and superposition, would expand the options for new, more precise algorithms.

    “Quantum systems can realize path integrals in real time, giving us access to large-scale simulations of the universe,” McGuigan said. “You can visualize the calculated wavefunction of the universe as it evolves forward without first formulating a full theory of quantum gravity.”

    Again, using the Qiskit package and access to IBM Q hardware, McGuigan and his collaborator Charles Kocher, a student at Brown University, employed a mix of classical computational methods and VQE to run varied experiments, including one that examined systems with gravity coupled to a boson field called an inflaton, a hypothetical particle that plays an important role in modern cosmology. Their work showed the hybrid VQE yielded wavefunctions consistent with the Wheeler-Dewitt equation, which mathematically combines quantum mechanics with Albert Einstein’s theory of relativity.

    Inspiration on an Expanding Scale

    While early quantum experiments are leading to different perspectives of the basics behind physics, quantum computing is expected to contribute major advances toward solving longstanding problems impacting DOE’s missions. Among them, it can be a tool for unveiling new materials, solving energy challenges, or adding to fundamental understandings (like time and temperature) in high energy physics and cosmology. In turn, these changes could cascade into more readily recognizable areas.

    For example, drug developers need more realized quantum mechanics to understand the structure of molecules. Quantum computers can enable discoveries by affording simulations of the full quantum mechanics that would provide a truly practical point of view.

    “There seems to always be interest in the basics behind physics,” McGuigan said. “It has been of interest to the public for millennia. Right now, the combination of theoretical expertise and actual technology is converging with quantum computing. Yet, it still is a very human endeavor.”

    For now, using near-term quantum computers to solve small thermo field problems or to take a new look at an old universe is inspiring researchers to scale up their algorithms as they do bigger things in science.

    “We get emboldened to do different things. We all do,” McGuigan said. “Other groups around the world, such as the Perimeter Institute in Canada and Universiteit van Amsterdam in the Netherlands, are already extending the thermo field double quantum algorithm to even bigger systems. With the emergence of large near-term quantum computers of 50-100 qubits, the goal is to run finite temperature simulations on realistic systems involving many particles. It is exciting to have an actual quantum computer to test these ideas and problems that we once had no solutions for. Quantum mechanics with no tradeoffs—that is what science is all about.”

    This research was supported by DOE’s Office of Science and the Supplemental Undergraduate Research Program (SURP) at Brookhaven Lab.

    Related:
    Miceli R and M McGuigan (2019).“Thermo field dynamics on a quantum computer.”
    IEEE Xplore Digital Library

    Kocher C and M McGuigan (2018). “Simulating 0+1 Dimensional Quantum Gravity on Quantum Computers: Mini-Superspace Quantum Cosmology and the World Line Approach in Quantum Field Theory.”
    IEEE Xplore Digital Library

    See the full article here .


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

    Please help promote STEM in your local schools.

    Stem Education Coalition

    BNL Campus

    Brookhaven campus

    BNL Center for Functional Nanomaterials

    BNL NSLS-II


    BNL NSLS II

    BNL RHIC Campus

    BNL/RHIC Star Detector

    BNL Phenix Detector

    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.

     
  • richardmitnick 9:54 am on December 6, 2019 Permalink | Reply
    Tags: , BNL, , , NSLS,   

    From D.O.E. Office of Science via Brookhaven National Lab: “The Big Questions: José Rodriguez on Catalysts” 

    Brookhaven National Lab

    December 4, 2019
    José Rodriguez

    1
    Distinguished Scientists Fellow José Rodriguez from Brookhaven Lab worked with fellow chemist Ping Liu to characterize structural and mechanistic details of a low-temperature catalyst for producing hydrogen gas from water and carbon monoxide.
    Image courtesy of Brookhaven National Laboratory.

    The Big Questions series features perspectives from the five recipients of the Department of Energy Office of Science’s 2019 Distinguished Scientists Fellows Award describing their research and what they plan to do with the award.

    Contributing Author Credit: José Rodriguez is a senior chemist at Brookhaven National Laboratory.

    How can we use some of the world’s brightest and strongest sources of synchrotron light to better understand the catalysts that speed up chemical reactions?

    Catalysts reduce the energy needed to make a chemical reaction take place. They’re essential in industry, used for making everything from fabric to synthetic plants. Catalysts are used in the production of many chemicals and fuels.

    Over the years, people have tried to understand how catalysts work in hopes of making them even better. To understand how a catalyst works, you need to see what happens at its active sites during chemical transformations. This is a very complex thing. You need a lot of tools to see how the catalyst changes over time, especially under harsh environmental conditions like high pressures and temperatures. Synchrotrons – incredibly powerful sources of light that produce X-rays – can provide a unique look into how these catalysts work.

    When I first arrived at the Department of Energy’s Brookhaven National Laboratory (BNL) 29 years ago, scientists were for the first time seriously proposing the use of a synchrotron to study catalysts. At that time, there was a lot of activity in the National Synchrotron Light Source (NSLS), a DOE Office of Science user facility.

    BNL NSLS

    At the end of my job interview, the head of BNL’s Chemistry Department asked, “How much money do you need to do this kind of science?” I said, “This is a very complex science. I need $750,000.” As a physical inorganic chemist, $50,000 was a lot of research money for him. But despite the price tag, he looked at me and said, “Okay, we’ll see what we can do.” He called up the person at DOE in charge of the catalysis program and said, “The young man looks very promising; we want to go into this new area. He needs $750,000.”

    With that funding, my team and I used NSLS to study catalysts in very controlled environments. We created these environments by putting the catalysts in specialized ultra-high vacuum chambers originally developed by NASA in the 1960s. After setting the inside of the chambers to the conditions we wanted, we put them in the synchrotron. The hard and soft X-rays from the synchrotron made it possible to study the structural, electronic, and chemical properties of the catalytic material as well as how those changed during the reaction process.

    There is still a big interest in the DOE Office of Science in understanding these catalytic materials. Since then, the NSLS has been replaced by its successor NSLS-II [below], which is also a DOE Office of Science user facility. With NSLS-II, we can use a high-intensity beam to do ultra-fast measurements. Now, we can make in-situ measurements of samples with highly diluted elements in times as short as milliseconds (a thousandth of a second). With this speed, we can now monitor catalysts’ properties during reactions very quickly. In catalysis research, the faster you can go, the better.

    With this fellowship, I’m going to expand the work we’re doing at the NSLS-II to better understand catalysts’ properties and how they change during reactions. While we’ve been working on this project for about five years, this new funding will help us move it forward. This work will involve not just the NSLS-II, but also researchers at BNL’s Center for Functional Nanomaterials (a DOE Office of Science user facility), the University of Kansas, Stony Brook University, and Columbia University. In the spirit of this fellowship, any equipment we develop will remain at the NSLS-II, where it will be available for the entire catalysis community to use.

    I think this project has the potential to make a big contribution to the field and I appreciate the opportunity the DOE’s Office of Science has provided me to lead it.

    See the full article here .


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

    Please help promote STEM in your local schools.

    Stem Education Coalition

    BNL Campus


    BNL Center for Functional Nanomaterials

    BNL NSLS-II


    BNL NSLS II

    BNL RHIC Campus

    BNL/RHIC Star Detector

    BNL RHIC PHENIX

    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.
    i1

     
  • richardmitnick 9:33 am on December 6, 2019 Permalink | Reply
    Tags: 3-D printed metals, , Alessandra Colli, , BNL, , Plasma 3-D printing,   

    From Brookhaven National Lab: Women in STEM- “Meet Alessandra Colli: Engineering Improvements in 3-D-printed Metals” 

    From Brookhaven National Lab

    December 3, 2019
    Karen McNulty Walsh
    kmcnulty@bnl.gov

    Colli seeks to merge materials risk analysis with data collected at world-class science tools to improve safety, reliability, and opportunities in metal additive manufacturing.

    1
    Alessandra Colli with National Synchrotron Light Source II beamline scientist Larry Carr at a beamline used for far-infrared spectroscopy (MET). This beamline will help characterize filter samples made by Obsidian AM, a company partnering with Brookhaven Lab to explore 3-D printing as a strategy for producing high-precision radiation filters for next-generation cosmic microwave background studies.

    With a background in electrical engineering and risk assessment, Alessandra Colli, a scientist at the U.S. Department of Energy’s (DOE) Brookhaven National Laboratory, wants airplane engines to function flawlessly, rockets to be reliable, and a new telescope to be sensitive to signals that could solve secrets of the universe. Her focus, however, is not on the electronic circuitry that powers these complex devices, but rather on improving the structure and function of their many metallic components.

    Colli is developing a strategy to leverage Brookhaven Lab’s materials-science capabilities and data analytics approaches to advance metal “additive manufacturing,” also known as 3-D printing. Compared with conventional metal manufacturing, 3-D printing offers great promise for building metal components with higher precision and greater reliability from the bottom up.

    “When you are talking about reliability, most of the time you look at the system level—how the part performs in the field, in the real-world application,” Colli said. “We want to bring in the basic materials science—the kinds of studies we can do at the National Synchrotron Light Source II (NSLS-II) and the Center for Functional Nanomaterials (CFN) to look at material properties and defects at very small scales—along with analytical techniques being developed by our Computational Science Initiative to efficiently sift through that data.”

    This approach could help scientists identify sources of material imperfections or weakness—and explore how different 3-D printing approaches or even new materials could improve a particular product.

    “Industrial partners could come in and we can help them solve specific issues using the enormous capabilities of our DOE Office of Science user facilities,” Colli said.

    3-D printed metals

    Once used mainly for creating prototypes or models, additive manufacturing is moving into the mainstream for a range of industrial and defense applications, so much so that many industrial players address it as the next industrial revolution in manufacturing, Colli said. Using 3-D printing to manufacture precision metal engine components, high-tech filters, or even construction hinges and brackets offers ways to reduce waste of feedstock material and dramatically improve design to achieve better performance of the final product, she noted.

    Instead of whittling down a larger block of metal, pouring molten material into a mold, or making separate components that must later be fastened together, 3-D printing uses a range of techniques to deposit the material layer by layer, printing only the desired object with little material wasted. The technology can create intricate objects and even allows construction from composite materials.

    But to ensure durability, strength, resistance to corrosion, or other characteristics important for specific applications, it’s essential to understand not just what the manufactured part looks like and how it works in its application, but also what’s going on inside—the characteristics of the material itself.

    Think about a piece that might be part of an airplane, or supporting parts for construction, part of a rocket engine or ship—these parts need extremely high reliability.

    “With additive manufacturing, there can be different types of defects—residual stress that creates tension in an area where you may not want it; porosity formed by bubbles that create a weak spot where the part can break. We have a range of techniques that can see these structural characteristics and the materials’ chemical composition. And we can study them under different environmental conditions, like pressure or high heat, that when combined with certain material characteristics can cause a failure,” Colli said.

    These tools can also help identify the best additive manufacturing processes for different applications, fine-tune manufacturing precision to take into account post-processing steps such as polishing or annealing, or explore new materials or combinations of materials that may improve functions.

    Building collaborations

    “There are lots of opportunities to grow collaborations with academic partners, industry, other departments at Brookhaven, and the user facilities here and at the other DOE Labs or research institutions around the world,” Colli said.

    As an example, Colli notes one collaboration already underway among scientists in Brookhaven’s Sustainable Energy Technologies Department, Physics Department, Instrumentation Division, NSLS-II, and Obsidian AM (a small spin-off company from Yale University in Connecticut) that hopes to develop filters for cosmic microwave background radiation [CMB].

    CMB per ESA/Planck

    These filters, designed for use in next-generation telescopes, are typically fabricated from metal as meshes or grids that get laminated together. Their job is to screen out signals from other forms of radiation so scientists can collect echoes of the radiation leftover from the Big Bang. Filtering out the “noise” will help physicists decipher details about neutrinos, dark matter, and general relativity.

    3
    Scientific exploration of new materials, composites, and 3-D printing processes along with engineering studies of new applications will open many opportunities in metal additive manufacturing. This approach could guide the development of 3-D printed materials with reliability in harsh environments, reduced size and weight, or other characteristics optimized for specific applications.

    “We are exploring plasma 3-D printing as a way to directly manufacture the full metamaterial for these filters. We’re starting by making sure we can print the metal part with optimal precision, but we are hoping to be able to print alternate layers of insulating material and metal grid directly using the same 3-D printing process,” Colli said.

    This approach could be applied to making other layered metamaterials and composites, such as high-temperature superconductors (promising materials that carry electric current with no resistance) and magnets.

    Colli is finalizing plans with professors at the North Carolina A&T State University and Rensselaer Polytechnic Institute to bring students in to learn about the various 3-D printing technologies, materials characterization tools such as x-ray diffraction, and approaches such as tensile stress testing. She is also collaborating with computational scientists to develop the tools and algorithms—many based on machine learning and other forms of “artificial intelligence”—to identify key indicators that will predict (and guide design to avoid) failure in additively manufactured metal components.

    Varied background, open mind

    “I’m not a materials scientist and I’m not a physicist, so to build this strategy and these collaborations, I had to learn everything too, including about the techniques; and I’m still learning,” Colli said. “My strength is to be able to understand both the small details and the big picture.”

    Colli attributes her wide-scale vision to the diversity of topics she studied early in her career: electrical power engineering for her master thesis and risk analysis for her Ph.D., the former at the Polytechnic University of Milan in Italy and the latter at Delft University of Technology in The Netherlands. “Diversifying things gives perspective in terms of what you can learn and what you can see. It really opens up your mind,” she said.

    She spent six years in The Netherlands developing methods to compare technological, environmental, and occupational risks of various energy technologies—fossil fuels, nuclear, and renewable energies such as solar. When she first came to Brookhaven Lab in 2011, she worked to integrate risk analysis into the economic side of evaluating energy systems.

    4
    Simulations of filters for cosmic microwave background radiation telescopes help identify the best configuration for optimal performance. This graphic shows one layer of the copper configuration simulated using CST Studio Suite, a 3-D electromagnetic analysis software program. The simulation determines what types of radiation get transmitted through or filtered out by the mesh.

    The proximity of the Northeast Solar Energy Research Center to NSLS-II first sparked her idea that understanding material properties might help address an energy challenge: why photovoltaic solar cells sometimes crack.

    “My idea was to apply my knowledge in risk analysis to reliability issues in photovoltaics. What is the impact of the different materials that make up these layered structures on the tendency of cracks to form and propagate, for example? We have the solar panels and the synchrotron right here to do the materials science testing,” she said.

    In 2018, Jim Misewich, Associate Laboratory Director for Energy and Photon Sciences (EPS), asked her to develop the Lab’s strategy for metal additive manufacturing as part of the EPS Growth plan. This opportunity gave her a chance to bring her idea of correlating material properties with performance and reliability to a new challenge.

    “I had to grow in my career, to go from being a scientist doing my job in the lab to develop a leadership mentality,” she said. With support from the Growth Office—including Elspeth McSweeney, Michael Cowell, and Jun Wang—she developed skills and sought professional training courses such as the Women in STEM Leadership program at Stony Brook University.

    “It was a year of enormous growth,” she said. “When people believe in you and they give you a chance, you feel obligated to give something back and to be successful. Supporting other people at the Lab helps us push each other.”

    Meaningful mentorship

    Colli puts these philosophies into practice as she mentors students through Brookhaven Lab’s Office of Educational Programs.

    “For me, research is always about teamwork. I am not the boss and you are not my slave; we work together, period. It’s a continuous exchange,” she said. “I let the students bring up ideas—have them tell me what we should do.”

    Sometimes suspicious of this approach and a bit lost without a predetermined path, Colli’s students often end up with an appreciation of what it means to be part of the scientific process.

    “I don’t care if they do perfect work or not. But when I see that they get engaged and they get passionate, that’s for me the best reward.”

    From her own experience, she also tells them, “Don’t be afraid if you end up in a different field because that may only increase your knowledge and open up your mind in different directions.”

    When she’s not developing new strategies at the Lab, Colli loves to connect with nature by hiking and especially riding her horse. “That is where I find my peace of mind,” she said.

    “I really love to be on Long Island, and I love the U.S.,” she added, noting that she hopes to become a full U.S. citizen as soon as she is eligible. “I still have two years to wait for that and I’m counting the days.”

    The metal additive manufacturing strategy is supported by Brookhaven Lab’s program development funds. NSLS-II and CFN are DOE Office of Science user facilities. The Computational Science Initiative is also supported by the DOE Office of Science.

    See the full article here .


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

    Please help promote STEM in your local schools.

    Stem Education Coalition

    BNL Campus


    BNL Center for Functional Nanomaterials

    BNL NSLS-II


    BNL NSLS II

    BNL RHIC Campus

    BNL/RHIC Star Detector

    BNL RHIC PHENIX

    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 9:45 am on November 22, 2019 Permalink | Reply
    Tags: , BNL, , ,   

    From Brookhaven National Lab: “Turning Up the Heat to Create New Nanostructured Metals” 

    From Brookhaven National Lab

    November 20, 2019
    Ariana Manglaviti
    amanglaviti@bnl.gov
    (631) 344-2347

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

    Scientists used heat to drive a spontaneous process in which different metals mixed to form 3-D interlocking nanostructures in thin films, with applications for catalysts, solar cells, and biomedical sensors.

    1
    Kim Kisslinger, Karen Chen-Wiegart, Bruce Ravel, Xiaojing Huang, Fernando Camino, Yong Chu, Hanfei Yan, Ming Lu, Chonghang Zhao, Cheng-Hung Lin, Mingzhao Liu, and Evgeny Nazaretski outside Brookhaven Lab’s Center for Functional Nanomaterials (CFN). The scientists used the Nanofabrication and Electron Microscopy facilities at the CFN and the Hard X-ray Nanoprobe and Beamline for Materials Measurement at the National Synchrotron Light Source II (pictured in the background) to synthesize and characterize metallic thin films with a bicontinuous structure formed via dealloying.

    Scientists have developed a new approach for making metal-metal composites and porous metals with a 3-D interconnected “bicontinuous” structure in thin films at size scales ranging from tens of nanometers to microns. Metallic materials with this sponge-like morphology—characterized by two coexisting phases that form interpenetrating networks continuing over space—could be useful in catalysis, energy generation and storage, and biomedical sensing. Called thin-film solid-state interfacial dealloying (SSID), the approach uses heat to drive a self-organizing process in which metals mix or de-mix to form a new structure. The scientists used multiple electron- and x-ray-based techniques (“multimodal analysis”) to visualize and characterize the formation of the bicontinuous structure.

    “Heating gives the metals some energy so that they can interdiffuse and form a self-supported thermodynamically stable structure,” explained Karen Chen-Wiegart, an assistant professor in Stony Brook University’s (SBU) Materials Science and Chemical Engineering Department, where she leads the Chen-Wiegart Research Group, and a scientist at the National Synchrotron Light Source II (NSLS-II)—a U.S. Department of Energy (DOE) Office of Science User Facility at Brookhaven National Laboratory. “SSID has been previously demonstrated in bulk samples (tens of microns and thicker) but results in a size gradient, with a larger structure on one side of the sample and a smaller structure on the other side. Here, for the first time, we successfully demonstrated SSID in a fully integrated thin-film processing, resulting in a homogenous size distribution across the sample. This homogeneity is needed to create functional nanostructures.”

    Chen-Wiegart is the corresponding author on a paper published online in Materials Horizons that is featured on the Nov. 18 online journal issue cover. The other collaborating institutions are the Center for Functional Nanomaterials (CFN)—another DOE Office of Science User Facility at Brookhaven Lab—and the National Institute of Standards and Technology (NIST).

    To demonstrate their process, the scientists prepared magnesium (Mg) and iron (Fe) and nickel (Ni) alloy thin films on silicon (Si) wafer substrates in the CFN Nanofabrication Facility. They heated the samples to high temperature (860 degrees Fahrenheit) for 30 minutes and then rapidly cooled them down to room temperature.

    “We found that Mg diffuses into the Fe-Ni layer, where it combines only with Ni, while Fe separates from Ni,” said first author Chonghang Zhao, a PhD student in the Chen-Wiegart Research Group. “This phase separation is based on enthalpy, an energy measurement that determines whether the materials are “happily” mixing or not, depending on properties such as their crystal structure and bonding configurations. The nanocomposite can be further treated to generate a nanoporous structure through chemically removing one of the phases.”

    2
    A schematic showing thin-film SSID for the Fe-Ni/Mg system. The thin films of Mg and Fe-Ni are layered on top of an Si substrate. Upon exposure to heat, the Mg dealloys Fe-Ni to form an Mg-Ni composite and pure Fe with a 3-D bicontinuous structure.

    Nanoporous structures have many applications, including photocatalysis. For example, these structures could be used to accelerate the reaction in which water is split into oxygen and hydrogen—a clean-burning fuel. Because catalytic reactions happen on material surfaces, the high surface area of the pores would improve reaction efficiency. In addition, because the nanosized “ligaments” are inherently interconnected, they do not need any support to hold them together. These connections could provide electrically conductive pathways.

    The team identified the dealloyed bicontinuous structure of Fe and Ni-Mg through complementary electron microscopy techniques at the CFN and x-ray synchrotron techniques at two NSLS-II beamlines: the Hard X-ray Nanoprobe (HXN) and Beamline for Materials Measurement (BMM).

    “Using the scanning mode in a transmission electron microscope (TEM), we rastered the electron beam over the sample in specific locations to generate 2-D elemental maps showing the spatial distribution of elements,” explained Kim Kisslinger, a technical associate in the CFN Electron Microscopy research group and the point of contact for the instrument.

    3
    The scientists used a scanning transmission electron microscope (STEM) to study the structure and composition of Fe-Ni films dealloyed by an Mg film. In particular, they combined high-angle annular dark-field (HAADF) imaging with energy-dispersive x-ray spectroscopy (EDS). HAADF imaging is sensitive to the atomic number of elements in the sample. Elements with a higher atomic number scatter more electrons, causing them to appear brighter in the resulting greyscale image. For the EDS maps, the different colors correspond to individual elements and the color intensity to their local relative concentration. STEM analysis revealed the formation of two phases: pure Fe (magenta) and an Ni-Mg (yellow-purple) composite.

    The team also used TEM to obtain electron diffraction patterns capturing the crystal structure and a scanning electron microscope (SEM) to study surface morphology.

    This initial analysis provided evidence of the formation of a bicontinuous structure locally in 2-D at high resolution. To further confirm that the bicontinuous structure was representative of the entire sample, the team turned to HXN beamline, which can provide 3-D information over a much larger region.

    “With HXN, we can focus hard, or high-energy, x-rays to a very tiny spot of about 12 nanometers,” said coauthor and HXN physicist Xiaojing Huang. “The world-leading spatial resolution of hard x-ray microscopy at HXN is sufficient to see the sample’s smallest structures, which range in size from 20 to 30 nanometers. Though TEM provides higher resolution, the field of view is limited. With the x-ray microscope, we were able to observe the 3-D element distributions within a bigger area so that we could confirm the homogeneity.”

    Measurements at HXN were conducted in a multimodality manner, with the simultaneous collection of x-ray scattering signals that reveal 3-D structure and fluorescence signals that are element-sensitive. Atoms emit fluorescence when they jump back to their lowest-energy (ground) state after being excited to an unstable higher-energy state in response to the x-ray energy. By detecting this characteristic fluorescence, scientists can determine the type and relative abundance of elements present at specific locations.


    A video based on the 3-D x-ray fluorescence nanotomography of the Fe-Ni thin film conducted at the Hard X-ray Nanoprobe.

    Coauthor and NIST Synchrotron Science Group physicist Bruce Ravel confirmed the sample’s chemical composition and obtained the precise chemical forms (oxidation states) of the elements at BMM, which is funded and operated by NIST. The x-ray absorption near-edge structure (XANES) spectra also showed the presence of pure Fe.

    Now that the scientists have shown that SSID works in thin films, their next step is to address the “parasitic” events they identified in the course of this study. For example, they discovered that Ni diffuses into the Si substrate, leading to voids, a kind of structural defect. They will also make pore structures from the metal-metal composites to demonstrate applications such as photocatalysis, and apply their approach to other metal systems, including titanium-based ones.

    This work was in part supported by a student fellowship by the Brookhaven-SBU Joint Photon Sciences Institute and the National Science Foundation’s Faculty Early Career Development Program and Metals and Metallic Nanostructures Program.

    See the full article here .


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

    Please help promote STEM in your local schools.

    Stem Education Coalition

    BNL Campus


    BNL Center for Functional Nanomaterials

    BNL NSLS-II


    BNL NSLS II

    BNL RHIC Campus

    BNL/RHIC Star Detector

    BNL RHIC PHENIX

    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 4:01 pm on November 8, 2019 Permalink | Reply
    Tags: "The Secret Behind Crystals that Shrink when Heated", A group from Caltech was using one method to explore this mystery at the Spallation Neutron Source At Oak Ridge National Laboratory., A long-standing materials science mystery: why certain crystalline materials shrink when heated., , BNL, , The BNL scientists paired up with the Caltech team to collect data at SNS using Caltech’s ScF3 samples to track how the distances between neighboring atoms changed with increasing temperature.   

    From Brookhaven National Lab: “The Secret Behind Crystals that Shrink when Heated” 

    From Brookhaven National Lab

    November 1, 2019

    Karen McNulty Walsh
    kmcnulty@bnl.gov
    (631) 344-8350

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

    Discovery yields new quantitative description of unusual behavior relevant to materials used in electronics, medicine, telecommunications, and more.

    1
    Igor Zaliznyak, a physicist in Brookhaven Lab’s Condensed Matter Physics and Materials Science Division (right), led a team of scientists including Alexei Tkachenko of the Lab’s Center for Functional Nanomaterials (left) to decipher the mechanism underlying scandium fluoride’s ability to shrink upon heating.

    Scientists at the U.S. Department of Energy’s Brookhaven National Laboratory have new experimental evidence and a predictive theory that solves a long-standing materials science mystery: why certain crystalline materials shrink when heated. Their work, just published in Science Advances, could have widespread application for matching material properties to specific applications in medicine, electronics, and other fields, and may even provide fresh insight into unconventional superconductors (materials that carry electric current with no energy loss).

    The evidence comes from precision measurements of the distances between atoms in crystals of scandium fluoride (ScF3), a material known for its unusual contraction under elevated temperatures (also known as “negative thermal expansion”). What the scientists discovered is a new type of vibrational motion that causes the sides of these cube-shaped, seemingly solid crystals to buckle when heated, thus pulling the corners closer together.

    “Normally as something heats up, it expands,” said Brookhaven physicist Igor Zaliznyak, who led the project. “When you heat something up, atomic vibrations increase in magnitude, and the overall material size increases to accommodate the larger vibrations.”

    That relationship, however, doesn’t hold for certain flexible materials, including chainlike polymers such as plastics and rubber. In those materials, increasing heat increases vibrations only perpendicular to the length of the chains (picture the sideways vibrations of a plucked guitar string). Those transverse vibrations pull the ends of the chains closer together, resulting in overall shrinkage.

    But what about scandium fluoride? With a solid, cubic crystalline structure, it looks nothing like a polymer—at least at first glance. In addition, a widespread assumption that the atoms in a solid crystal have to maintain their relative orientations, no matter what the crystal size, left physicists confounded to explain how this material shrinks when heated.

    2
    This animation shows how solid crystals of scandium fluoride shrink upon heating. While the bonds between scandium (green) and fluorine atoms (blue) remain relatively rigid, the fluorine atoms along the sides of the cubic crystals oscillate independently, resulting in a wide range of distances between neighboring fluorine atoms. The higher the temperature, the greater the buckling in the sides of the crystals leading to the overall contraction (negative thermal expansion) effect.

    Neutrons and a dedicated student to the rescue

    A group from the California Institute of Technology (Caltech) was using one method to explore this mystery at the Spallation Neutron Source (SNS), a DOE Office of Science user facility at Oak Ridge National Laboratory. Measuring how beams of neutrons, a type of subatomic particle, scatter off the atoms in a crystal can give valuable information about their atomic-scale arrangement. It’s particularly useful for lightweight materials like fluorine that are invisible to x-rays, Zaliznyak said.

    3
    Scientists used neutron scattering at the Spallation Neutron Source at Oak Ridge National Laboratory to investigate why certain crystalline materials shrink when heated. Credit: Oak Ridge National Laboratory

    Hearing about this work, Zaliznyak noted that his colleague, Emil Bozin, an expert in a different neutron-scattering analysis technique, could probably advance understanding of the problem. Bozin’s method, known as “pair distribution function,” describes the probability of finding two atoms separated by a certain distance in a material. Computational algorithms then sort through the probabilities to find the structural model that best fits the data.

    Zaliznyak and Bozin paired up with the Caltech team to collect data at SNS using Caltech’s ScF3 samples to track how the distances between neighboring atoms changed with increasing temperature.

    David Wendt, a student who began a Brookhaven Lab High School Research Program internship in Zaliznyak’s lab following his sophomore year in high school (now a freshman at Stanford University), handled much of the data analysis. He continued working on the project throughout his high-school days, earning the position of first author on the paper.

    “David basically reduced the data to the form that we could analyze using our algorithms, fitted the data, composed a model to model the positions of the fluorine atoms, and did the statistical analysis to compare our experimental results to the model. The amount of work he did is like what a good postdoc would do!” Zaliznyak said.

    “I am very grateful for the opportunity Brookhaven Lab provided me to contribute to original research through their High School Research Program,” Wendt said.

    Results: “soft” motion in a solid

    The measurements showed that the bonds between scandium and fluorine don’t really change with heating. “In fact, they expand slightly,” Zaliznyak said, “which is consistent with why most solids expand.”

    But the distances between adjacent fluorine atoms became highly variable with increasing temperature.

    “We were looking for evidence that the fluorine atoms were staying in a fixed configuration, as had always been assumed, and we found quite the opposite!” Zaliznyak said.

    4
    Additional coauthors on the study included (from left) Kate Page, formerly of Oak Ridge National Laboratory, Brookhaven Lab physicist Emil Bozin, and ORNL instrument scientist Joerg Neuefeind. Credit: Genevieve Martin/Oak Ridge National Laboratory

    Alexei Tkachenko, an expert in the theory of soft condensed matter at Brookhaven Lab’s Center for Functional Nanomaterials (another Office of Science user facility) made essential contributions to the explanation for this unexpected data.

    Since the fluorine atoms appeared not to be confined to rigid positions, the explanation could draw on a much older theory originally developed by Albert Einstein to explain atomic motions by considering each individual atom separately. And surprisingly, the final explanation shows that heat-induced shrinkage in ScF3 bears a remarkable resemblance to the behavior of soft-matter polymers.

    “Since every scandium atom has a rigid bond with fluorine, the ‘chains’ of scandium-fluoride that form the sides of the crystalline cubes (with scandium at the corners) act similar to the rigid parts of a polymer,” Zaliznyak explained. The fluorine atoms at the center of each side of the cube, however, are unrestrained by any other bonds. So, as temperature increases, the “underconstrained” fluorine atoms are free to oscillate independently in directions perpendicular to the rigid Sc-F bonds. Those transverse thermal oscillations pull the Sc atoms at the corners of the cubic lattice closer together, resulting in shrinkage similar to that observed in polymers.

    Thermal matching for applications

    This new understanding will improve scientists’ ability to predict or strategically design a material’s thermal response for applications where temperature changes are expected. For example, materials used in precision machining should ideally show little change in response to heating and cooling to maintain the same precision across all conditions. Materials used in medical applications, such as dental fillings or bone replacements, should have thermal expansion properties that closely match those of the biological structures in which they are embedded (think how painful it would be if your filling expanded while your tooth contracted when drinking hot coffee!). And in semiconductors or undersea fiberoptic transmission lines, the thermal expansion of insulating materials should match that of the functional materials to avoid impeding signal transmission.

    Zaliznyak notes that an underconstrained open framework architecture like that in ScF3 is also present in copper-oxide and iron-based superconductors—where crystal lattice vibrations are thought to play a role in these materials’ ability to carry electric current with no resistance.

    “The independent oscillation of atoms in these open-framework structures may contribute to these materials’ properties in ways we can now calculate and understand,” Zaliznyak said. “They might actually explain some of our own experimental observations that still remain a mystery in these superconductors,” he added.

    “This work profoundly benefitted from the important advantages of the DOE national laboratories—including unique DOE facilities and our ability to have long-time-span projects where important contributions accumulate over time to culminate in a discovery,” Zaliznyak said. “It represents the unique confluence of different expertise among the coauthors, including a dedicated high-school student intern, which we were able to integrate synergistically for this project. It would not have been possible to successfully carry out this research without the expertise provided by all the team members.”

    Brookhaven Lab’s role in this work was funded by the DOE Office of Science.

    See the full article here .


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

    Please help promote STEM in your local schools.

    Stem Education Coalition

    BNL Campus


    BNL Center for Functional Nanomaterials

    BNL NSLS-II


    BNL NSLS II

    BNL RHIC Campus

    BNL/RHIC Star Detector

    BNL RHIC PHENIX

    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 3:21 pm on November 8, 2019 Permalink | Reply
    Tags: "Tethered Chem Combos Could Revolutionize Artificial Photosynthesis", , “You just dip the electrode coated with the chromophores into a solution in which the catalyst is suspended and the tethers on the two types of molecules find one another and link up”, BNL, , Getting hydrogen atoms to recombine as pure hydrogen gas (H2) is a step toward solar-powered clean-fuel generation., Production of hydrogen gas fuel via artificial photosynthesis and a platform for testing different combos to further improve efficiency.   

    From Brookhaven National Lab: “Tethered Chem Combos Could Revolutionize Artificial Photosynthesis” 

    From Brookhaven National Lab

    November 4, 2019
    Karen McNulty Walsh,
    kmcnulty@bnl.gov
    (631) 344-8350

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

    New approach improves efficiency of converting sunlight to hydrogen fuel; provides platform for testing different combos of light-absorbers and catalysts.

    1
    Brookhaven Lab chemist Javier Concepcion and Lei Wang, a graduate student at Stony Brook University, devised a scheme for assembling light-absorbing molecules and water-splitting catalysts on a nanoparticle-coated electrode. The result: production of hydrogen gas fuel via artificial photosynthesis and a platform for testing different combos to further improve efficiency.

    Scientists at the U.S. Department of Energy’s Brookhaven National Laboratory have doubled the efficiency of a chemical combo that captures light and splits water molecules so the building blocks can be used to produce hydrogen fuel. Their study, selected as an American Chemical Society “Editors’ Choice” that will be featured on the cover* of the Journal of Physical Chemistry C, provides a platform for developing revolutionary improvements in so-called artificial photosynthesis—a lab-based mimic of the natural process aimed at generating clean energy from sunlight.

    In natural photosynthesis, green plants use sunlight to transform water (H2O) and carbon dioxide (CO2) into carbohydrates such as sugar and starches. The energy from the sunlight is stored in the chemical bonds holding those molecules together.

    Many artificial photosynthesis strategies start by looking for ways to use light to split water into its constituents, hydrogen and oxygen, so the hydrogen can later be combined with other elements—ideally the carbon from carbon dioxide—to make fuels. But even getting the hydrogen atoms to recombine as pure hydrogen gas (H2) is a step toward solar-powered clean-fuel generation.

    To achieve water splitting, scientists have been exploring a wide range of light-absorbing molecules (also called chromophores, or dyes) paired with chemical catalysts that can pry apart water’s very strong hydrogen-oxygen bonds. The new approach uses molecular “tethers”—simple carbon chains that have a high affinity for one another—to attach the chromophore to the catalyst. The tethers hold the particles close enough together to transfer electrons from the catalyst to the chromophore—an essential step for activating the catalyst—but keeps them far enough apart that the electrons don’t jump back to the catalyst.


    Generating fuel from sunlight: First, tin oxide (SnO2) nanoparticles get coated with a titanium dioxide (TiO2) shell. Next, scientists coat the nanoparticles with light-absorbing dye molecules that have dangling tethers. Then they add catalyst molecules that attach by their own tethers. In the final setup, sunlight excites the dye, kicking electrons from dye to nanoparticle shell, nanoparticle core, and then out of the electrode via a wire. The electron-deficient dye, in turn, grabs electrons from the catalyst. Once the catalyst has lost four electrons, it can steal four electrons from two water molecules, thereby splitting water into hydrogen ions and oxygen. At a second electrode, the hydrogen ions recombine with electrons to produce H2 — hydrogen gas fuel. Animation credit: Stony Brook University graduate student and study coauthor Lei Wang

    “Electrons move fast, but chemical reactions are much slower. So, to give the system time for the water-splitting reaction to take place without the electrons moving back to the catalyst, you have to separate those charges,” explained Brookhaven Lab chemist Javier Concepcion, who led the project.

    In the complete setup, the chromophores (tethered to the catalyst) are embedded in a layer of nanoparticles on an electrode. Each nanoparticle is made of a core of tin dioxide (SnO2) surrounded by a titanium dioxide (TiO2) shell. These different components provide efficient, stepwise shuttling of electrons to keep pulling the negatively charged particles away from the catalyst and sending them to where they are needed to make fuel.

    Here’s how it works from start to finish: Light strikes the chromophore and gives an electron enough of a jolt to send it from the chromophore to the surface of the nanoparticle. From there the electron moves to the nanoparticle core, and then out of the electrode through a wire. Meanwhile, the chromophore, having lost one electron, pulls an electron from the catalyst. As long as there’s light, this process repeats, sending electrons flowing from catalyst to chromophore to nanoparticle to wire.

    Each time the catalyst loses four electrons, it becomes activated with a big enough positive charge to steal four electrons from two water molecules. That breaks the hydrogen and oxygen apart. The oxygen bubbles out as a gas (in natural photosynthesis, this is how plants make the oxygen we breathe!) while the hydrogen atoms (now ions because they are positively charged) diffuse through a membrane to another electrode. There they recombine with the electrons carried by the wire to produce hydrogen gas—fuel!

    Building on experience

    The Brookhaven team had tried an earlier version of this chromophore-catalyst setup [ACS Energy Letters] where the light-absorbing dye and catalyst particles were connected much more closely with direct chemical bonds instead of tethers.

    “This was very difficult to do, taking many steps of synthesis and purification, and it took several months to make the molecules,” Concepcion said. “And the performance was not that good in the end.”

    In contrast, attaching the carbon-chain tethers to both molecules allows them to self-assemble.

    “You just dip the electrode coated with the chromophores into a solution in which the catalyst is suspended and the tethers on the two types of molecules find one another and link up,” said Stony Brook University graduate student Lei Wang, a coauthor on the current paper and lead author on a paper published earlier this year [Journal of the American Chemical Society] that described the self-assembly strategy.

    The new paper includes data showing that the system with tethered connections is considerably more stable than the directly connected components, and it generated twice the amount of current—the number of electrons flowing through the system.

    “The more electrons you generate from the light coming in, the more you have available to generate hydrogen fuel,” Concepcion said.

    The scientists also measured the amount of oxygen produced.

    “We found that this system, using visible light, is capable of reaching remarkable efficiencies for light-driven water splitting,” Concepcion said.

    But there’s still room for improvement, he noted. “What we’ve done to this point works to make hydrogen. But we would like to move to making higher value hydrocarbon fuels.” Now that they have a system where they can easily interchange components and experiment with other variables, they are set to explore the possibilities.

    “One of the most important aspects of this setup is not just the performance, but the ease of assembly,” Concepcion said.

    “Because these combinations of chromophores and catalysts are so easy to make, and the tethers give us so much control over the distance between them, now we can study, for example, what is the optimal distance. And we can do experiments combining different chromophores and catalysts without having to do much complex synthesis to find the best combinations,” he said. “The versatility of this approach will allow us to do fundamental studies that would not have been possible without this system.”

    This research was funded by the DOE Office of Science and was conducted in collaboration with scientists from the Alliance for Molecular PhotoElectrode Design for Solar Fuels EFRC, a DOE Office of Science Energy Frontier Research Center at the University of North Carolina, Chapel Hill. UNC scientists provided the core-shell nanoparticles. Design and synthesis of the system were done at Brookhaven Lab; transient kinetics and photoelectrochemistry studies were carried out at UNC.

    See the full article here .


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

    Please help promote STEM in your local schools.

    Stem Education Coalition

    BNL Campus


    BNL Center for Functional Nanomaterials

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    BNL NSLS II

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    BNL RHIC PHENIX

    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 12:26 pm on November 1, 2019 Permalink | Reply
    Tags: "A Superconductor That "Remembers" its Electronic Charge Arrangement", A cuprate known as LBCO for the compounds it contains: lanthanum; barium; copper; and oxygen., , BNL, CDW-charge density wave, , HTSCs-high-temperature superconductors, ,   

    From Brookhaven National Lab: “A Superconductor That “Remembers” its Electronic Charge Arrangement” 

    From Brookhaven National Lab

    October 30, 2019
    Laura Mgrdichian
    mgrdichian@gmail.com

    New information on charge order in a high-temperature superconductor may lead to a fuller understanding of these materials’ electronic behavior.

    1
    The Coherent Soft X-ray Scattering (CSX) beamline at NSLS-II offers the researchers the right tools to probe charge ordering phenomena in quantum materials such as high-temperature superconductors with unprecedented precision. The researcher here aside the CSX scattering station are Stuart Wilkins (left) and Xiaoqian Chen, Mark Dean, Andi Barbour and Vivek Thampy (right from back to front). Other co-authors not shown include X-Ray Scattering Group Leader Ian Robinson and Neutron Scattering Group Leader John Tranquada.

    In the field of superconductivity – the ability of a material to conduct electricity with virtually zero resistance – the so-called high-temperature superconductors (HTSCs) are possible candidates for a new generation of advanced technologies. One subset of these, the “cuprates,” which are crystalline materials based on planes of copper oxide, are particularly promising. But scientists still need to learn much more about these materials before mainstream, room-temperature applications are possible. Currently, even the “high-temperature” superconductors must be chilled to very, very cold temperatures by everyday standards.

    Working at the U.S. Department of Energy’s (DOE) Brookhaven National Laboratory, researchers from Brookhaven and University College London recently discovered something new and very surprising about one type of periodic electric charge arrangement, which coexists with superconductivity in cuprates, known as a charge density wave (CDW). They found that the specific CDW order within their sample was “remembered” when the sample was repeatedly heated past the temperature where the CDW disappears. This discovery opens a new avenue of research into how these intriguing materials work, bringing scientists one step closer to a complete picture of electronic behavior in cuprates.

    “It would be like melting a pile of ice cubes and then refreezing them – and discovering that they refroze into an identical pile of cubes, even down at the microscopic level,” explained Brookhaven Lab physicist Claudio Mazzoli, one of the researchers involved in the study. “Nobody would expect to see that.”

    Mazzoli and his co-researchers describe their work in the March 29, 2019 online edition of Nature Communications.

    The electronic behavior of the cuprates, as with all HTSCs, is quite complex. As the name implies, the electrons that make up a CDW form a periodic standing-wave pattern. CDWs have been observed in nearly all the cuprates, but their role in superconductivity is still not fully understood. Do they compete with superconductivity? Do they participate in it? Do they hinder superconductivity in certain ways and possibly add to it in others? Scientists are still working this out.

    “In the HTSCs, any arrangement of electrons is of interest to researchers,” said Brookhaven physicist Mark Dean, another of the paper’s authors. “The goal is to investigate these arrangements and tune them – or perhaps remove them – so that the superconducting transition temperature of the material can approach, or maybe surpass, room temperature. To do this, we must learn as much as we can about the electrons’ behavior and their structures in HTSCs.”

    2
    Claudio Mazzoli (left) and Mark Dean (right) used the TARDIS experimental chamber at NSLS-II’s Coherent Soft X-ray Scattering (CSX) beamline to investigate the behavior of charge density waves in a specific high-temperature superconductor.

    One thing that researchers do know is that cuprates containing the same copper oxide planes – but arranged in a slightly different way – may have CDWs with dramatically different properties. It seems, then, that the part of the crystal lattice that hosts the CDW has an effect on the CDW.

    Here, the group set out to learn more about the relationship between the material’s lattice structure and CDW behavior. Their model system was a cuprate known as LBCO for the compounds it contains: lanthanum, barium, copper, and oxygen. LBCO has a transition temperature – the temperature below which it displays the CDW, and above which it does not – of 54 degrees Kelvin (K) (although equivalent to about -360 degrees Fahrenheit, this temperature is still relatively high in the superconductor world).

    The group wanted to find out how imperfections in the LBCO crystal lattice can stabilize the CDW. They were interested in a well-known lattice distortion that occurs in the material: a tilt in the octahedral shape formed by bound copper and oxygen atoms. This tilt tends to anchor the CDW to the lattice such that it orients in a certain direction; it appears that the CDW may be sensitive to the spatial inhomogeneities, or domains, of the lattice. This relationship between the CDW and the domains, as suggested by the temperature behavior uncovered in this study, may be unique to LBCO. It will be very important to understand whether this is a general feature of the cuprates.

    The group cycled their LBCO sample through a range of temperatures, repeatedly heating and cooling it, while probing it with x-rays at Brookhaven’s National Synchrotron Light Source II (NSLS-II), a DOE Office of Science User Facility. At the Coherent Soft X-Ray Scattering (CSX) beamline, they used a technique known as coherent resonant x-ray diffraction, in which x-rays scatter from different domains in the CDW spatial arrangement, interfere with each other, and form a “speckle” pattern that is captured by a special camera. Analyzing this pattern yields information on the CDW’s features.

    3
    The schematic shows how a speckle pattern is measured: first the coherent x-ray beam delivered by the beamline is focused onto the sample, then the x-rays are scattered by the sample at a specific angle (sensitive to the charge density wave presence)and captured by the CCD detector. The pinhole provides a mask, allowing the researchers to illuminate only a small, specific area of the sample.

    This task – directly observing a CDW while tracking its changes, over a range of temperatures – is collectively very challenging, in large part due to the very short distances that characterize the features of a CDW. NSLS-II is uniquely suited to this type of investigation due to the coherent nature of the light it produces, meaning the light waves travel in unison rather than out-of-sync and jumbled. Older light sources do not have such highly coherent beams.

    The speckle analysis revealed that the specific CDW order present below 54 K returned even when the sample was repeatedly cycled through much higher temperatures, up to about 240 K (about -28 °F). The researchers think that the structural changes that take place in the crystal below 240 K create a “pinning landscape” that anchors the CDW to the lattice.

    “Our work opens a new route for studying the complex interplay between charge and lattice degrees of freedom in superconducting cuprates,” said the paper’s lead author, Xiaoqian Chen, a researcher in Brookhaven’s Condensed Matter Physics and Materials Science Department at the time this study was performed (she is now working at Lawrence Berkeley National Laboratory). “It is also a great demonstration of how NSLS-II can be used to study quantum phases of materials and their spectacular, unexpected properties.”

    “This result emphasizes the vital importance of the role of nanoscale domains in high-temperature superconductivity. Without the domain pinning effects that have been observed, the CDW might carry current and further disrupt the superconductivity,” added co-author Ian Robinson, a physicist at Brookhaven as well as at University College London. “Imaging these subtle ‘phase’ domain structures is still in its infancy and this work highlights the need to develop better imaging techniques so that structural details can be seen directly.”

    The preparation of the sample used in this study was done at Brookhaven’s Center for Functional Nanomaterials. Additionally, a small portion of this work was performed at Argonne National Laboratory’s Advanced Photon Source. Both are DOE Office of Science User Facilities.

    See the full article here .


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

    Please help promote STEM in your local schools.

    Stem Education Coalition

    BNL Campus


    BNL Center for Functional Nanomaterials

    BNL NSLS-II


    BNL NSLS II

    BNL RHIC Campus

    BNL/RHIC Star Detector

    BNL RHIC PHENIX

    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 3:08 pm on October 25, 2019 Permalink | Reply
    Tags: , , BNL, NSLS II Celebrates its 5th Anniversary   

    From Brookhaven National Lab: “NSLS-II Celebrates its 5th Anniversary” 

    From Brookhaven National Lab

    October 23, 2019
    Stephanie Kossman
    skossman@bnl.gov

    In just five years, 28 beamlines came online, over 1,800 different experiments ran, and nearly 3,000 scientists conducted research at the National Synchrotron Light Source II.

    1
    An aerial view of NSLS-II. The facility is large enough to fit Yankee Stadium inside its half-mile-long ring.

    On this day five years ago, the National Synchrotron Light Source II (NSLS-II) achieved “first light”—its first successful delivery of x-ray beams. Signaling the start of operations at NSLS-II—one of the world’s most advanced synchrotron light sources—Oct. 23, 2014 marked a new era of synchrotron science.

    “It is astonishing to me how much we have accomplished in just five years,” said NSLS-II Director John Hill. “Every day when I come to work, I am proud of what we have achieved through the expertise, dedication and passion that everyone here brings to NSLS-II.”

    The legacy of light sources at Brookhaven Lab

    Synchrotron light sources like NSLS-II produce extremely intense light (from infrared to x-rays), which scientists can use to “see” the inner structural, chemical, and electronic makeup of materials, down to the atomic scale. From protein structures to chemical processes in batteries, light sources illuminate scientific mysteries of all kinds. But in decades past, this ultrabright light could only be produced as a byproduct of particle accelerators and it was widely considered to be a nuisance.

    As the scientific value of ultrabright synchrotron light became well-recognized in the early 1970s, two scientists at the U.S. Department of Energy’s (DOE) Brookhaven National Laboratory, Renate Chasman and G. Kenneth Green, pushed the field forward by developing a novel magnet configuration for synchrotron storage rings that optimized the brightness of light sources. Their design became the basis for Brookhaven’s National Synchrotron Light Source (NSLS), NSLS-II’s predecessor, and later led to the rapid growth of major light source facilities around the world.

    NSLS was one of the first research facilities designed and built specifically for producing ultrabright light or “synchrotron radiation.” NSLS was also the first DOE facility dedicated to “user” research; rather than tackling a single large scientific question, NSLS served many users who conducted individual experiments and came from diverse areas of science and the world. The model gave birth to the DOE Office of Science User Facility program and, ultimately, research at NSLS was awarded two Nobel Prizes.

    2
    An aerial view of NSLS when the facility was still running. Today, the building is the home of Brookhaven Lab’s Computational Science Initiative.

    Building on the legacy of NSLS, NSLS-II was designed to deliver x-rays 10,000 times brighter than its predecessor. The key to the upgraded design is NSLS-II’s half-mile-long accelerator ring that enables the facility to produce extremely narrow x-ray beams. At its largest point, the beam at NSLS-II is only a few dozen microns wide—the width of a human hair. NSLS-II’s advanced accelerator design also provides unprecedented beam stability, giving the facility a world record for beam spot size and opening doors to many new types of scientific experiments.

    Five years of growth and success at NSLS-II

    In NSLS-II’s first five years, scientists and engineers came together to bring 28 experimental stations, called beamlines, into operations, building out nearly half of the facility’s experimental floor. That means that at any given time, 28 different experiments can run simultaneously at NSLS-II. When the facility is fully built out, NSLS-II will accommodate up to 60 different experiments at once.

    3
    How the National Synchrotron Light Source II works. In a synchrotron light source, a “beamline” is a long pipe in which light travels outwards from the facility’s storage ring, where electrons circulate at nearly the speed of light. At NSLS-II, each beamline connects to two hutches: the optical hutch, where scientists can adjust the light to their experiment’s specifications, and the experimental hutch, where scientists set up their samples to be illuminated by the light.

    NSLS-II’s large capacity for beamlines not only enables more scientists to access the facility’s ultrabright light at once, but it also provides the space and flexibility needed to develop highly specialized scientific instruments that accommodate unique and difficult-to-run experiments.

    One of the most notable of these highly specialized beamlines at NSLS-II is the Hard X-ray Nanoprobe (HXN). Housed in its own satellite building that was specially constructed to provide extraordinary stability, HXN gave NSLS-II a world record for beam spot size and offers world-leading spatial resolution to users. The beamline enables scientists to investigate everything from microelectronics to cell membranes.

    3
    The Hard X-ray Nanoprobe (HXN) at NSLS-II.

    Another remarkable beamline that is unique to NSLS-II is the Soft Inelastic X-ray Scattering (SIX) beamline. Like HXN, SIX is also enclosed in its own satellite building, but for a different reason. This beamline is built with a 50-foot-long spectrometer arm that moves from one end of the building to the other, providing world-leading energy resolution. The beamline’s design enables scientists to probe the electronic structure of materials to advance research on quantum materials and superconductors.

    4
    The Soft Inelastic X-ray Scattering (SIX) beamline at NSLS-II.

    With so many specialized and world-class tools available at NSLS-II, visiting researchers can benefit by taking their experiments to multiple beamlines to compare and combine datasets and achieve a more holistic view of their samples.

    “NSLS-II recognizes the need for comprehensive studies on materials, which means researchers need to use more than one technique to uncover the properties and behaviors of materials,” Hill said. “I am very pleased that our users can now request multiple beamlines on a single proposal, what we call a ‘multimodal’ proposal.”

    From biology to materials science, researchers from all areas of science have come to NSLS-II to take advantage of these capabilities. In the facility’s first five years, staff scientists and visiting researchers have unlocked new protein structures, studied nanoscale phenomena in electronic and information technologies, studied energy materials across multiple length and time scales at once, and watched chemical catalysts work in real-time.

    Sometimes, the images produced at NSLS-II are as beautiful as they are informative. Earlier this year, scientists at Carnegie Mellon University collaborated with NSLS-II to determine how nanomaterials could be used to tackle global food security challenges. Using the Submicron Resolution X-ray Spectroscopy (SRX) beamline and the X-ray Fluorescence Microprobe (XFM) beamline, the team produced images in which key elements in crop samples fluoresced. By studying these images, the scientists were able to determine how nanoparticles influenced the movement of metals throughout the crops, suggesting ways to target the delivery of nutrients to specific plant organs.

    5
    Data images produced by XFM. (Left) Data from the Carnegie Mellon research described above. (Right) Scans of a leaflet of P. vittata (an arsenic hyperaccumulator) from an additional study, showing the concentrations of potassium (green), arsenic (red), and calcium (blue).

    In March, scientists at NSLS-II identified the cause of battery cathode degradation in nickel-rich materials. The team used the Inner-Shell Spectroscopy (ISS) and X-ray Powder Diffraction (XPD) beamlines at NSLS-II to “see” the chemical environment around nickel atoms in a cathode material, and determined inhomogeneities in nickel’s oxidation states led to the degradation. Their work could help improve lithium-ion batteries, which are used to power everything from consumer electronics to electric vehicles.

    6
    Brookhaven chemists and NSLS-II scientists are shown at the ISS beamline, where the battery research was conducted. Pictured from front to back are Eli Stavitski, Xiao-Qing Yang, Xuelong Wang, and Enyuan Hu.

    In addition to collaborating with universities and other national laboratories on individual studies, NSLS-II has established strong working relationships with outside institutions to fund and operate new beamlines at the facility. For example, the National Institute of Standards and Technology owns and operates three beamlines at NSLS-II that enable scientists to “see” detailed views of chemical reactions. Case Western Reserve University operates one beamline and collaborates with NSLS-II on two additional beamlines to provide scientists with a suite of biological imaging endstations. One of NSLS-II’s most notable partnerships, however, is with Brookhaven’s own Center for Functional Nanomaterials (CFN), another DOE Office of Science User Facility. CFN currently operates three beamlines in partnership with NSLS-II that are specialized for characterizing nanomaterials.

    New science on the horizon

    In the years to come, scientific collaborations will continue to be key for NSLS-II. For example, a new cryo-electron microscope (cryo-EM) center funded by New York State, called the Laboratory of Biomolecular Structure (LBMS), is currently under construction at Brookhaven Lab, adjacent to NSLS-II. Combining the suite of biological beamlines at NSLS-II with the cryo-EMs at LBMS will offer researchers complementary techniques to study biological systems. The goal is to reveal unprecedented information on the structure and dynamics of the engines of life.

    Also under construction at NSLS-II is a new beamline funded by the New York State Energy Research and Development Authority, called the High Energy Engineering X-Ray Scattering (HEX) beamline. HEX will be a powerful and versatile tool to advance energy storage and conversion research, such as battery development and materials engineering. The beamline will provide extremely energetic x-rays that can penetrate steel casings of full-size batteries so scientists can image atomic structures under working conditions and in real time.

    “Looking to the future, I see NSLS-II becoming an even larger hub for materials characterization of all kinds,” Hill said. “Our high-end beamlines and expert staff offer many opportunities for partnerships and collaborations. At the end of the day, this is what makes our science strong: the brightest minds, together, focusing on the biggest challenges in science.”

    See the full article here .


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

    Please help promote STEM in your local schools.

    Stem Education Coalition

    BNL Campus


    BNL Center for Functional Nanomaterials

    BNL NSLS-II


    BNL NSLS II

    BNL RHIC Campus

    BNL/RHIC Star Detector

    BNL RHIC PHENIX

    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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