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  • richardmitnick 4:11 pm on April 17, 2021 Permalink | Reply
    Tags: "German National Supercomputing Centre Provides Computational Muscle to Look for Cracks in the Standard Model of Physics", , , DOE’s Brookhaven National Laboratory, Gauss Centre for Supercomputing [Gauß-Zentrum für Supercomputing] (DE), Jülich Supercomputing Centre [Forschungszentrum Jülich ] (DE), Leibniz Supercomputing Centre [Leibniz-Rechenzentrum] (DE), Magnetic moment of subatomic particles called muons, Muon g-2 collaboration, , ,   

    From Gauss Centre for Supercomputing [Gauß-Zentrum für Supercomputing] (DE): “German National Supercomputing Centre Provides Computational Muscle to Look for Cracks in the Standard Model of Physics” 

    From Gauss Centre for Supercomputing [Gauß-Zentrum für Supercomputing] (DE)

    April 09, 2021
    Eric Gedenk

    Physicists have spent 20 years trying to more precisely measure the so-called “magnetic moment” of subatomic particles called muons. Findings published this week call into question long-standing assumptions of particle physics.

    1
    Does the magnetic moment of muons fit into our understanding of the laws governing the physical world around us? Credit: Uni Wuppertal / thavis gmbh.

    Since the 1970s, the Standard Model of Physics has served as the basis from which particle physics are investigated.

    Standard Model of Particle Physics, Quantum Diaries

    .

    Both experimentalists and theoretical physicists have tested the Standard Model of Particle Physics’s accuracy, and it has remained the law of the land when it comes to understanding how the subatomic world behaves.

    This week, cracks formed in that foundational set of assumptions. Researchers of the “Muon g-2” collaboration from the DOE’s Fermi National Accelerator Laboratory (US) published further experimental findings that show that muons—heavy subatomic relatives of electrons—may have a larger “magnetic moment” than earlier Standard Model estimates had predicted, indicating that an unknown particle or force might be influencing the muon. The work builds on anomalous results first uncovered 20 years ago at DOE’s Brookhaven National Laboratory, and calls into question whether the Standard Model needs to be rewritten.

    DOE’s Fermi National Accelerator Laboratory(US) Muon g-2 studio. As muons race around a ring at the Muon g-2 studio, their spin axes twirl, reflecting the influence of unseen particles.

    Meanwhile, researchers in Germany have used Europe’s most powerful high-performance computing (HPC) infrastructure to run new and more precise lattice quantum chromodynamics (lattice QCD) calculations of muons in a magnetic field. The team found a different value for the Standard Model prediction of muon behaviour than what was previously accepted. The new theoretical value is in agreement with the FNAL experiment, suggesting that a revision of the Standard Model is not needed. The results are now published in Nature.

    The team primarily used the supercomputer JUWELS at the Jülich Supercomputing Centre (JSC), with the computational time provided by the Gauss Centre for Supercomputing (GCS) as well at JSC’s JURECA system, along with extensive computations performed at the other two GCS sites—on Hawk at the High-Performance Computing Center Stuttgart (HLRS) and on SuperMUC-NG at the Leibniz Supercomputing Centre (LRZ).

    JURECA supercomputer at Jülich Supercomputing Centre [Forschungszentrum Jülich ] (DE)

    SuperMUC-NG, GCS@LRZ, Lenovo supercomputer at the Leibniz Supercomputing Centre [Leibniz-Rechenzentrum] (DE)

    SuperMUC-NG, GCS@LRZ, Lenovo supercomputer Germany at the Leibniz Supercomputing Centre [Leibniz-Rechenzentrum] (DE)

    Both the experimentalists and theoretical physicists agreed that further research must be done to verify the results published this week. One thing is clear, however: the HPC resources provided by GCS were essential for the scientists to achieve the precision necessary to get these groundbreaking results.

    “For the first time, lattice results have a precision comparable to these experiments. Interestingly our result is consistent with the new FNAL experiment, as opposed to previous theory results, that are in strong disagreement with it,” said Prof. Kalman Szabo, leader of the Helmholtz research group, “Relativistic Quantum Field Theory” at JSC and co-author of the Nature publication. “Before deciding the fate of the Standard Model, one has to understand the theoretical differences, and new lattice QCD computations are inevitable for that.”

    Minor discrepancies, major implications

    When DOE’s Brookhaven National Laboratory(US) researchers recorded unexplained muon behaviour in 2001, the finding left physicists at a loss—the muon, a subatomic particle 200 times heavier than an electron, showed stronger magnetic properties than predicted by the Standard Model of Physics. While the initial finding suggested that muons may be interacting with previously unknown subatomic particles, the results were still not accurate enough to definitely claim a new finding.

    Over the next 20 years, heavy investments in new, hyper-sensitive experiments done at particle accelerator facilities as well as increasingly sophisticated approaches based in theory have sought to confirm or refute the BNL group’s findings. During this time, a research group led by the University of Wuppertal [Universität Wuppertal] (DE)’s Prof. Zoltan Fodor, another co-author of the Nature paper, was progressing with big steps in lattice QCD simulations on the supercomputers provided by GCS. “Though our results on the muon g-2 are new, and have to be thoroughly scrutinized by other groups, we have a long record of computing various physical phenomena in quantum chromodynamics.” said Prof. Fodor. “Our previous major achievements were computing the mass of the proton, the proton-neutron mass difference, the phase diagram of the early universe and a possible solution for the dark matter problem. These paved the way to our most recent result.”

    Lattice QCD calculations allow researchers to accurately plot subatomic particle movements and interactions with extremely fine time resolution. However, they are only as precise as computational power allows—in order to perform these calculations in a timely manner, researchers have had to limit some combination of simulation size, resolution, or time. As computational resources have gotten more powerful, researchers have been able to do more precise simulations.

    “This foundational work shows that Germany’s world-class HPC infrastructure is essential for doing world-class science in Europe”, said Prof. Thomas Lippert, Director of the Jülich Supercomputing Centre, Professor for Quantum Computing and Modular Supercomputing at Goethe University [Goethe-Universität] Frankfurt(DE), current Chairman of the GCS Board of Directors, and also co-author of the Nature paper. “The computational resources of GCS not only play a central role in deepening the discourse on muon measurements, but they help European scientists and engineers become leaders in many scientific, industrial, and societal research areas.”

    While Fodor, Lippert, Szabo, and the team who published the Nature paper currently use their calculations to cool the claims of physics beyond the Standard Model, the researchers are also excited to continue working with international colleagues to definitively solve the mystery surrounding muon magnetism. The team anticipates that even more powerful HPC systems will be necessary to prove the existence of physics beyond the Standard Model. “The DOE’s Fermi National Accelerator Laboratory(US) experiment will increase the precision by a factor of four in two years. We theorists have to keep up with this pace if we want to fully exploit the new physics discovery potential of muons.” Szabo said.

    Further Information:
    Physical Review Letters

    See the full article here.

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    The Gauss Centre for Supercomputing (DE) combines the three national supercomputing centres HLRS (High Performance Computing Center Stuttgart [Hochleistungsrechnungszentrum Stuttgart] (DE), JSC (Jülich Supercomputing Centre [Forschungszentrum Jülich ] (DE)), and LRZ (Leibniz Supercomputing Centre [Leibniz-Rechenzentrum](DE) into Germany’s Tier-0 supercomputing institution. Each GCS member centre host supercomputers well beyond the 1 Petaflops performance mark. Concertedly, the three centres provide the largest and most powerful supercomputing infrastructure in all of Europe to serve a wide range of industrial and research activities in various disciplines. They also provide top-class training and education for the national as well as the European High Performance Computing (HPC) community.

    GCS is the German member of PRACE (Partnership for Advance Computing in Europe), an international non-profit association consisting of 25 member countries, whose representative organizations create a pan-European supercomputing infrastructure, providing access to computing and data management resources and services for large-scale scientific and engineering applications at the highest performance level.

    Gauss Centre for Supercomputing LRZ – Leibniz Supercomputing Centre Garching

    GCS is jointly funded by the German Federal Ministry of Education and Research and the federal states of Baden-Württemberg, Bavaria and North Rhine-Westphalia.

    GCS has its headquarters in Berlin, Germany.

     
  • richardmitnick 10:10 pm on January 25, 2021 Permalink | Reply
    Tags: "RHIC Run 21- Pushing the Limits at the Lowest Collision Energy", An extraordinary soup of free quarks and gluons-a substance that mimics what the early universe was like some 14 billion years ago., , Beam Energy Scan II (BES-II)- a three-year systematic study of what happens when gold ions-gold atoms stripped of their electrons-collide at various low energies., , DOE’s Brookhaven National Laboratory, , , Out of the five energies of BES-II—9.8; 7.3; 5.75; 4.6; and 3.85 billion electron volts-or GeV-this year’s run at 3.85 GeV is the most difficult one., , , , RHIC’s highest collision energies (up to 200 GeV) produce temperatures more than 250000 times hotter than the center of the Sun., The goal for this run is to maximize collision rates at the lowest energy ever achieved at RHIC.   

    From DOE’s Brookhaven National Laboratory: “RHIC Run 21- Pushing the Limits at the Lowest Collision Energy” 

    From DOE’s Brookhaven National Laboratory

    January 25, 2021
    Karen McNulty Walsh,
    kmcnulty@bnl.gov
    (631) 344-8350

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

    Final stage of Beam Energy Scan II will collect low-energy collision data needed to understand the transition of ordinary nuclear matter into a soup of free quarks and gluons.

    1
    Accelerator physicist Chuyu Liu, the run coordinator for this year’s experiments at the Relativistic Heavy Ion Collider (RHIC), in the Main Control Room of the collider-accelerator complex at Brookhaven National Laboratory.

    Accelerator physicists are preparing the Relativistic Heavy Ion Collider (RHIC) [below], a DOE Office of Science user facility for nuclear physics research at DOE’s Brookhaven National Laboratory, for its 21st year of experiments, set to begin on or about February 3, 2021. Instead of producing high-energy particle smashups, the goal for this run is to maximize collision rates at the lowest energy ever achieved at RHIC.

    “Run 21 is the final step of Beam Energy Scan II (BES-II), a three-year systematic study of what happens when gold ions—gold atoms stripped of their electrons—collide at various low energies,” said Brookhaven physicist Lijuan Ruan, co-spokesperson for RHIC’s STAR [below] experiment collaboration.

    Nuclear physicists will examine the BES-II data, along with data from RHIC’s high-energy collisions, to map out how these collisions transform ordinary protons and neutrons into an extraordinary soup of free quarks and gluons—a substance that mimics what the early universe was like some 14 billion years ago. By turning the collision energy down, RHIC physicists can change the temperature and other variables to study how these conditions affect the transition from ordinary matter to early-universe hot quark-and-gluon soup.

    “Out of the five energies of BES-II—9.8, 7.3, 5.75, 4.6, and 3.85 billion electron volts, or GeV—this year’s run at 3.85 GeV is the most difficult one,” said Brookhaven Lab accelerator physicist Chuyu Liu, the run coordinator. That’s because “RHIC’s beams of gold ions are really difficult to hold together at the lowest energy,” he explained.

    In Run 21, the accelerator team will use a variety of innovative components and schemes to maintain the lifetime and intensity of the colliding ion beams under challenging conditions. Read on to learn more about RHIC’s Run 21 science goals and the accelerator features that will make the science possible.

    2
    Mapping nuclear phase changes is like studying how water changes under different conditions of temperature and pressure (net baryon density for nuclear matter). RHIC’s collisions “melt” protons and neutrons to create quark-gluon plasma (QGP). STAR physicists are exploring collisions at different energies, turning the “knobs” of temperature and baryon density, to look for signs of a “critical point.” That’s a set of conditions where the type of transition between ordinary nuclear matter and QGP changes from a smooth crossover observed at RHIC’s highest energies (gradual melting) to an abrupt “first order” phase change that’s more like water boiling in a pot.

    Scanning the transition

    As Ruan explained, the quest to map out the phases of nuclear matter and the transitions between them is somewhat similar to studying how water molecules transform from solid ice to liquid water and gaseous steam at different temperatures and pressures. But nuclear matter is trickier to study.

    “We need a powerful particle collider and sophisticated detector systems to create and study the most extreme forms of nuclear matter,” she said. “Thanks to the incredible versatility of RHIC, we can use the ‘knob’ of collision energy and the intricate particle-tracking capabilities of the STAR detector to conduct this systematic study.”

    RHIC’s highest collision energies (up to 200 GeV) produce temperatures more than 250,000 times hotter than the center of the Sun. Those collisions “melt” the protons and neutrons that make up gold atoms’ nuclei, creating an exotic phase of nuclear matter called a quark-gluon plasma (QGP). In QGP, quarks and gluons are “free” from their ordinary confinement within protons and neutrons, and they flow with virtually no resistance—like a nearly perfect liquid.

    But QGP lasts a mere fraction of a second before “freezing out” to form new particles. RHIC physicists piece together details of how the melting and refreezing happen by taking “snapshots” of the particles that stream out of these collisions.

    By systematically lowering the collision energy, the physicists are looking for signs of a so-called “critical point.” This would be a set of conditions where the type of transition between ordinary nuclear matter and QGP changes from the smooth crossover observed at RHIC’s highest energies (picture butter melting gradually on a counter), to an abrupt “first order” phase change (think of how water boils suddenly at a certain temperature and holds that temperature until all the molecules evaporate).

    “Theorists have predicted that certain key measurements at RHIC will exhibit dramatic event-by-event fluctuations when we approach this critical point,” Ruan said.

    Some RHIC physicists liken these fluctuations to the turbulence an airplane experiences when it moves from smooth air into a bank of clouds and then back out again. Measurements from phase I of RHIC’s Beam Energy Scan (BES-I, with data collected between 2010 and 2017) revealed tantalizing hints of such turbulence. But because collisions are hard to achieve at low energies, the data from BES-I aren’t strong enough to draw definitive conclusions.

    Now, in BES-II, a host of accelerator improvements have been implemented to maximize low-energy collision rates.

    Cooling the ions

    One of the innovations that Chuyu Liu and the other Collider-Accelerator Department (C-AD) physicists managing RHIC operations will take advantage of in Run 21 is a first-of-its-kind beam-cooling system. This Low Energy RHIC electron Cooling (LEReC) system operated at full capacity for the first time in last year’s RHIC run, making it the world’s first implementation of electron cooling in a collider. But it will be even more important for the lowest-of-low collision energies this year.

    3
    A host of accelerator improvements have been implemented to maximize RHIC’s low-energy collision rates. These include a series of components that inject a stream of cool electron bunches into the ion beams in these cooling sections of the two RHIC rings. The cool electrons extract heat to counteract the tendency of RHIC’s ions to spread out, thereby maximizing the chances the ions will collide when the beams cross at the center of RHIC’s STAR detector. (Photo taken 2019.)

    “The longer the beam stays at low energy, the more ‘intra-beam scattering’ and ‘space charge’ effects degrade the beam quality, reducing the number of circulating ions,” said Liu. Simplistic translation: The positively charged ions tend to repel one another. (Remember: The ions are atoms of gold stripped of their electrons, leaving a lot of net positive charge from the 79 protons in the nucleus.) The scattering and the repulsive space charge cause the ions to spread out, essentially heating up the beam as it makes its way around the 2.4-mile-circumference RHIC accelerator. And spread-out ions are less likely to collide.

    “The LEReC system operates somewhat similar to the way the liquid running through your home refrigerator extracts heat to keep your food cool,” said Wolfram Fischer, Associate Chair for Accelerators in C-AD, “but the technology needed to achieve this beam cooling is quite a bit more complicated.”

    A series of components (special lasers and a photocathode gun) produces bunches of relatively cool electrons, which are accelerated to match the bunching and near-light-speed pace of RHIC’s ions. Transfer lines inject the cool electrons into the stream of ion bunches—first in one RHIC ring, then, after making a 180-degree turn, into the other. As the particles mix, the electrons extract heat, effectively squeezing the spread-out ion bunches back together. The warmed-up electron bunches then get dumped and replaced with a new cool batch.

    “To add more flexibility for cooling optimization during this year’s run at RHIC’s lowest energy, where the space-charge effects and beam lifetime degradation are concerns for both the electrons and the ions, we installed a new ‘second harmonic’ radiofrequency (RF) cavity in the electron accelerator,” said Alexei Fedotov, the accelerator physicist who led the LEReC project.

    These cavities generate the radio waves that push the electrons along their path, with the higher (second harmonic) frequency helping to flatten out the longitudinal profile of the electron bunches. “This should help to reduce the space charge effect in the electron beams to achieve better cooling performance at low energy,” Fedotov said.

    “We plan to commission the new electron beam transport line in late January and start cooling ions with the new electron beam setup in early February,” he added.

    More accelerator advances

    Similarly, third-harmonic RF cavities installed in the ion accelerator rings will help to flatten the longitudinal profile of the ion bunches, reducing their peak intensity and space charges, Liu explained. “With that, more bunch intensity can be injected into RHIC to produce higher luminosity—a measure closely tied to collision rates,” he said.

    The accelerator team will also be commissioning a new bunch-by-bunch feedback system to help stabilize the beam for a better lifetime. “This system measures how each ion bunch deviates from the center of the beam pipe, and then applies a proportional correction signal through a component called a kicker to nudge each bunch back to where it should be,” Liu said.

    All this cooling and nudging will counteract the ions’ tendency to spread, which maximizes chances of collisions happening when the two beams cross at the center of STAR.

    “This run will bring together many of the advances we’ve been working on at RHIC to meet the challenging conditions of low-energy collisions,” said Fischer. “STAR would have preferred to test the lowest energy first, but we needed to learn everything possible (and develop the electron cooling system) before we could embark on operation at the most difficult energy.”

    See the full article here .


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    Brookhaven 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.

     
  • richardmitnick 10:13 am on January 22, 2021 Permalink | Reply
    Tags: "Light-induced Twisting of Weyl Nodes Switches on Giant Electron Current", , , DOE’s Brookhaven National Laboratory, , , , Weyl and Dirac semimetals   

    From DOE’s Brookhaven National Laboratory and DOE’s Ames Laboratory with University of Alabama Birmingham: “Light-induced Twisting of Weyl Nodes Switches on Giant Electron Current” 

    From DOE’s Brookhaven National Laboratory

    and

    From DOE’s Ames Laboratory

    with

    1

    January 18, 2021
    Ariana Manglaviti
    amanglaviti@bnl.gov
    (631) 344-2347

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

    1
    Collaborating scientists at the U.S. Department of Energy’s Ames Laboratory, Brookhaven Laboratory and the University of Alabama Birmingham used laser pulses to twist the crystal lattice of a Weyl semimetal, switching on a giant electron current that appears to be nearly dissipationless. The discovery and control of such properties brings these materials another step closer to use in applications such as quantum computing.

    Scientists at the U.S. Department of Energy’s Ames Laboratory and collaborators at Brookhaven National Laboratory and the University of Alabama at Birmingham have discovered a new light-induced switch that twists the crystal lattice of the material, switching on a giant electron current that appears to be nearly dissipationless. The discovery was made in a category of topological materials that holds great promise for spintronics, topological effect transistors, and quantum computing.

    Weyl and Dirac semimetals can host exotic, nearly dissipationless, electron conduction properties that take advantage of the unique state in the crystal lattice and electronic structure of the material that protects the electrons from doing so. These anomalous electron transport channels, protected by symmetry and topology, don’t normally occur in conventional metals such as copper. After decades of being described only in the context of theoretical physics, there is growing interest in fabricating, exploring, refining, and controlling their topologically protected electronic properties for device applications. For example, wide-scale adoption of quantum computing requires building devices in which fragile quantum states are protected from impurities and noisy environments. One approach to achieve this is through the development of topological quantum computation, in which qubits are based on “symmetry-protected” dissipationless electric currents that are immune to noise.

    “Light-induced lattice twisting, or a phononic switch, can control the crystal inversion symmetry and photogenerate giant electric current with very small resistance,” said Jigang Wang, senior scientist at Ames Laboratory and professor of physics at Iowa State University. “This new control principle does not require static electric or magnetic fields, and has much faster speeds and lower energy cost.”

    “This finding could be extended to a new quantum computing principle based on the chiral physics and dissipationless energy transport, which may run much faster speeds, lower energy cost and high operation temperature.” said Liang Luo, a scientist at Ames Laboratory and first author of the paper.

    Wang, Luo, and their colleagues accomplished just that, using terahertz (one trillion cycles per second) laser light spectroscopy to examine and nudge these materials into revealing the symmetry switching mechanisms of their properties.

    In this experiment, the team altered the symmetry of the electronic structure of the material, using laser pulses to twist the lattice arrangement of the crystal. This light switch enables “Weyl points” in the material, causing electrons to behave as massless particles that can carry the protected, low dissipation current that is sought after.

    “We achieved this giant dissipationless current by driving periodic motions of atoms around their equilibrium position in order to break crystal inversion symmetry,” says Ilias Perakis, professor of physics and chair at the University of Alabama at Birmingham. “This light-induced Weyl semimetal transport and topology control principle appears to be universal and will be very useful in the development of future quantum computing and electronics with high speed and low energy consumption.”

    “What we’ve lacked until now is a low energy and fast switch to induce and control symmetry of these materials,” said Qiang Li, Group leader of the Brookhaven National Laboratory’s Advanced Energy Materials Group. “Our discovery of a light symmetry switch opens a fascinating opportunity to carry dissipationless electron current, a topologically protected state that doesn’t weaken or slow down when it bumps into imperfections and impurities in the material.”

    The research is further discussed in the paper “A Light-induced Phononic Symmetry Switch and Giant Dissipationless Topological Photocurrent in ZrTe5,” authored by L. Luo, D. Cheng, B. Song, L.-L. Wang, C. Vaswani, P. M. Lozano, G. Gu, C. Huang, R. H. J. Kim, Z. Liu, J.-M. Park, Y. Yao, K.-M. Ho, I. E. Perakis, Q. Li and J. Wang; and published in Nature Materials.

    Terahertz photocurrent and laser spectroscopy experiments and model building were performed at Ames Laboratory. Sample development and magneto-transport measurements were conducted by Brookhaven National Laboratory. Data analysis was conducted by the University of Alabama at Birmingham. First-principles calculations and topological analysis were conducted by the Center for the Advancement of Topological Semimetals, an Energy Frontier Research Center funded by the DOE Office of Science.

    Ames Laboratory is a U.S. Department of Energy Office of Science National Laboratory operated by Iowa State University. Ames Laboratory creates innovative materials, technologies and energy solutions. We use our expertise, unique capabilities and interdisciplinary collaborations to solve global problems.

    Ames Laboratory is supported by the Office of Science of the U.S. Department of Energy. The Office of Science is the single largest supporter of basic research in the physical sciences in the United States, and is working to address some of the most pressing challenges of our time. For more information, please visit https://energy.gov/science.

    See the full article here .


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    Ames Laboratory is a government-owned, contractor-operated research facility of the U.S. Department of Energy that is run by Iowa State University.

    For more than 60 years, the Ames Laboratory has sought solutions to energy-related problems through the exploration of chemical, engineering, materials, mathematical and physical sciences. Established in the 1940s with the successful development of the most efficient process to produce high-quality uranium metal for atomic energy, the Lab now pursues a broad range of scientific priorities.

    Ames Laboratory is a U.S. Department of Energy Office of Science national laboratory operated by Iowa State University. Ames Laboratory creates innovative materials, technologies and energy solutions. We use our expertise, unique capabilities and interdisciplinary collaborations to solve global problems.

    Ames Laboratory is supported by the Office of Science of the U.S. Department of Energy. The Office of Science is the single largest supporter of basic research in the physical sciences in the United States, and is working to address some of the most pressing challenges of our time. For more information, please visit science.energy.gov.

    Brookhaven 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.

     
  • richardmitnick 8:49 am on January 15, 2021 Permalink | Reply
    Tags: "Science Begins at Brookhaven Lab's New Cryo-EM Research Facility", , , , , , DOE’s Brookhaven National Laboratory, ,   

    From DOE’s Brookhaven National Laboratory: “Science Begins at Brookhaven Lab’s New Cryo-EM Research Facility” 

    From DOE’s Brookhaven National Laboratory

    January 14, 2021
    Cara Laasch
    laasch@bnl.gov
    (631) 344-8458

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

    Brookhaven Lab’s Laboratory for BioMolecular Structure is now open for experiments with visiting researchers using two NY State-funded cryo-electron microscopes.

    1
    Brookhaven Lab Scientist Guobin Hu loaded the samples sent from researchers at Baylor College of Medicine into the new cryo-EM at LBMS.

    On January 8, 2021, the U.S. Department of Energy’s (DOE) Brookhaven National Laboratory welcomed the first virtually visiting researchers to the Laboratory for BioMolecular Structure (LBMS), a new cryo-electron microscopy facility. DOE’s Office of Science funds operations at this new national resource, while funding for the initial construction and instrument costs was provided by NY State. This state-of-the-art research center for life sciences imaging offers researchers access to advanced cryo-electron microscopes (cryo-EM) for studying complex proteins as well as the architecture of cells and tissues.

    Many modern advances in biology, medicine, and biotechnology were made possible by researchers learning how biological structures such as proteins, tissues, and cells interact with each other. But to truly reveal their function as well as the role they play in diseases, scientists need to visualize these structures at the atomic level. By creating high-resolution images of biological structure using cryo-EMs, researchers can accelerate advances in many fields including drug discovery, biofuel development, and medical treatments.

    This first group of researchers from Baylor College of Medicine used the high-end instruments at LBMS to investigate the structure of solute transporters. These transporters are proteins that help with many biological functions in humans, such as absorbing nutrients in the digestive system or maintaining excitability of neurons in the nervous system. This makes them critical for drug design since they are validated drug targets and many of them also mediate drug uptake or export. By revealing their structure, the researchers gain more understanding for the functions and mechanisms of the transporters, which can improve drug design. The Baylor College researchers gained access to the cryo-EMs at LBMS through a simple proposal process.

    “Our experience at LBMS has been excellent. The facility has been very considerate in minimizing user effort in submission of the applications, scheduling of microscope time, and data collection,” said Ming Zhou, Professor in the Department of Biochemistry of Molecular Biology at Baylor College of Medicine.

    All researchers from academia and industry can request free access to the LBMS instruments and collaborate with the LBMS’ expert staff.

    2
    During the measurement of the samples, the LBMS team interacted with the scientists from Baylor College of Medicine through Zoom to coordinate the research.

    “By allowing science-driven use of our instruments, we will meet the urgent need to advance the molecular understanding of biological processes, enabling deeper insight for bio-engineering the properties of plants and microbes or for understanding disease,” said Liguo Wang, Scientific Operations Director of the LBMS. “We are very excited to welcome our first visiting researchers for their remote experiment time. The researchers received time at our instruments through a call for general research proposals at the end of August 2020. Since September, we have been running the instruments only for COVID-19-related work and commissioning.”

    LBMS has two cryo-electron microscopes—funded by $15 million from NY State’s Empire State Development—and the facility has space for additional microscopes to enhance its capabilities in the future. In recognition of NY State’s partnership on the project and to bring the spirit of New York to the center, each laboratory room is associated with a different iconic New York State landmark, including the Statue of Liberty, the Empire State Building, the Stonewall National Monument, and the Adam Clayton Powell Jr. State Office Building.

    “By dedicating our different instruments to New York landmarks, we wanted to acknowledge the role the State played in this new national resource and its own unique identity within Brookhaven Lab,” said Sean McSweeney, LBMS Director. “Brookhaven Lab has a number of facilities offering scientific capabilities to researchers from both industry and academia. In our case, we purposefully built our center next to the National Synchrotron Light Source II, which also serves the life science research community. We hope that this co-location will promote interactions and synergy between scientists for exchanging ideas on improving performance of both facilities.”

    Brookhaven’s National Synchrotron Light Source II (NSLS-II) [below] is a DOE Office of Science User Facility and one of the most advanced synchrotron light sources in the world. NSLS-II enables scientists from academia and industry to tackle the most important challenges in quantum materials, energy storage and conversion, condensed matter and materials physics, chemistry, life sciences, and more by offering extremely bright light, ranging from infrared light to x-rays. The vibrant structural biology and bio-imaging community at NSLS-II offers many complementary techniques for studying a wide variety of biological samples.

    “At NSLS-II, we build strong partnership with our sister facilities, and we are looking forward to working closely with our colleagues at LBMS. For our users, this partnership will offer them access to expert staff at both facilities as well as to a versatile set of complementary techniques,” said NSLS-II Director John Hill. “NSLS-II has a suite of highly automated x-ray crystallography and solution scattering beamlines as well as imaging beamlines with world-leading spatial resolution. All these beamlines offer comprehensive techniques to further our understanding of biological system. Looking to the future, we expect to combine other x-ray techniques with the cryo-EM data to provide unprecedented information on the structure and dynamics of the engines of life.”

    LBMS operations are funded by the U.S. Department of Energy’s Office of Science. NSLS-II is a DOE Office of Science user facility.

    See the full article here .


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

    Please help promote STEM in your local schools.

    Stem Education Coalition

    Brookhaven 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.

     
  • richardmitnick 10:35 am on January 8, 2021 Permalink | Reply
    Tags: "Cell Membrane Proteins Imaged in 3-D", , , , DOE’s Brookhaven National Laboratory, , LBT-lanthanide-binding tag,   

    From DOE’s Brookhaven National Laboratory: “Cell Membrane Proteins Imaged in 3-D” 

    From DOE’s Brookhaven National Laboratory

    April 13, 2020 [From Year End Wrap-up]
    Stephanie Kossman
    skossman@bnl.gov
    (631) 344-8671

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

    Scientists used lanthanide-binding tags to image proteins at the level of a cell membrane, opening new doors for studies on health and medicine.

    1
    Ultrabright x-rays revealed the concentration of erbium (yellow) and zinc (red) in a single E.coli cell expressing a lanthanide-binding tag and incubated with erbium.

    A team of scientists including researchers at the National Synchrotron Light Source II (NSLS-II) [below]—a U.S. Department of Energy (DOE) Office of Science User Facility at DOE’s Brookhaven National Laboratory—have demonstrated a new technique for imaging proteins in 3-D with nanoscale resolution. Their work, published in the Journal of the American Chemical Society, enables researchers to identify the precise location of proteins within individual cells, reaching the resolution of the cell membrane and the smallest subcellular organelles.

    In the structural biology world, scientists use techniques like x-ray crystallography and cryo-electron microscopy to learn about the precise structure of proteins and infer their functions, but we don’t learn where they function in a cell,” said corresponding author and NSLS-II scientist Lisa Miller. “If you’re studying a particular disease, you need to know if a protein is functioning in the wrong place or not at all.”

    The new technique developed by Miller and her colleagues is similar in style to traditional methods of fluorescence microscopy in biology, in which a molecule called green fluorescent protein (GFP) can be attached to other proteins to reveal their location. When GFP is exposed to UV or visible light, it fluoresces a bright green color, illuminating an otherwise “invisible” protein in the cell.

    “Using GFP, we can see if a protein is in subcellular structures that are hundreds of nanometers in size, like the nucleus or the cytoplasm,” Miller said, “but structures like a cell membrane, which is only seven to 10 nanometers in size, are difficult to see with visible light tags like GFP. To see structures the size of 10 nanometers in a cell, you benefit greatly from the use of x-rays.”

    To overcome this challenge, researchers at NSLS-II teamed up with scientists at the Massachusetts Institute of Technology (MIT) and Boston University (BU) who developed an x-ray-sensitive tag called a lanthanide-binding tag (LBT). LBTs are very small proteins that can bind tightly to elements in the lanthanide series, such as erbium and europium.

    2
    Part of the research team is shown at NSLS-II’s Hard X-ray Nanoprobe. Pictured from left to right are Xiaojing Huang, Randy Smith, Yong Chu, Hanfei Yan, Tiffany Victor, and Lisa Miller.

    “Unlike GFP, which fluoresces when exposed to UV or visible light, lanthanides fluoresce in the presence of x-rays,” said lead author Tiffany Victor, a research associate at NSLS-II. “And since lanthanides do not occur naturally in the cell, when we see them with the x-ray microscope, we know the location of our protein of interest.”

    The researchers at NSLS-II, MIT, and BU worked together to combine LBT technology with x-ray-fluorescence.

    “Although LBTs have been used extensively over the last decade, they’ve never been used for x-ray fluorescence studies,” Miller said.

    Beyond obtaining higher resolution images, x-ray fluorescence simultaneously provides chemical images on all trace elements in a cell, such as calcium, potassium, iron, copper, and zinc. In other studies, Miller’s team is researching how trace elements like copper are linked to neuron death in diseases like Alzheimer’s. Visualizing the location of these elements in relation to specific proteins will be key to new findings.

    In addition to their compatibility with x-rays, LBTs are also beneficial for their relatively small size, compared to visible light tags.

    “Imagine you had a tail attached to you that was the size of your whole body, or bigger,” Miller said. “There would be a lot of normal activities that you’d no longer be able to do. But if you only had to walk around with a tiny pig’s tail, you could still run, jump, and fit through doorways. GFP is like the big tail—it can be a real impediment to the function of a many proteins. But these little lanthanide-binding tags are almost invisible.”

    To demonstrate the use of LBTs for imaging proteins in 3-D with nanoscale resolution, the researchers at MIT and BU tagged two proteins in a bacterial cell—one cytoplasmic protein and one membrane protein. Then, Miller’s team studied the sample at the Hard X-ray Nanoprobe (HXN) beamline at NSLS-II and the Bionanoprobe beamline at the Advanced Photon Source (APS)—a DOE Office of Science User Facility at DOE’s Argonne National Laboratory.

    ANL Advanced Photon Source.

    “HXN offers the world-leading x-ray focus size, which goes down to about 12 nanometers. This was critical for imaging the bacterial cell in 3-D with nanoscale resolution,” said Yong Chu, lead beamline scientist at HXN. “We also developed a new way of mounting the cells on a specialized sample holder in order to optimize the efficiency of the measurements.”

    By coupling the unparalleled resolution of HXN with the capabilities of LBTs, the team was able to image both of the tagged proteins. Visualizing the cell membrane protein proved LBTs can be seen at a high resolution, while imaging the cytoplasmic protein showed LBTs could also be visualized within the cell.

    “At high concentrations, lanthanides are toxic to cells,” Victor said, “so it was important for us to show that we could treat cells with a very low lanthanide concentration that was nontoxic and substantial enough to make it past the cell membrane and image the proteins we wanted to see.”

    Now, with this new technique demonstrated successfully, scientists hope to be able to use LBTs to image other proteins within the cell at a resolution of 10 nanometers.

    This study was supported by the U.S. Department of Energy and the National Science Foundation. Operations at NSLS-II and APS are supported by DOE’s 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

    Brookhaven 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.

     
  • richardmitnick 10:22 am on December 24, 2020 Permalink | Reply
    Tags: "Nikhil Tiwale- Practicing the Art of Nanofabrication", , “I think of lithography as architecture at the micro or nanoscale” said Tiwale., BNL Center for Functional Nanomaterials (CFN), DOE’s Brookhaven National Laboratory, , Nanofabrication, , , , The art of lithography   

    From DOE’s Brookhaven National Laboratory: “Nikhil Tiwale- Practicing the Art of Nanofabrication” 

    From DOE’s Brookhaven National Laboratory

    December 21, 2020
    Ariana Manglaviti
    amanglaviti@bnl.gov

    As a postdoctoral researcher in the Center for Functional Nanomaterials at Brookhaven Lab [below], Tiwale fabricates new kinds of microelectronic device components.

    1
    Nikhil Tiwale holds a nanopatterned silicon wafer in the Nanofabrication Facility cleanroom of Brookhaven Lab’s Center for Functional Nanomaterials (CFN). Here, he processes resists (materials that are sensitive to external stimuli such as light, electrons), patterns them using lithography, and transfers lithographic patterns onto substrates like silicon through etching to build functional electronic devices.

    From a young age, Nikhil Tiwale was curious about how technologies—particularly computers—are put together to deliver certain functions. At the same time, Tiwale found himself drawn to graphic art, fascinated with how the convergence of geometric shapes gives rise to intricate designs. He would spend hours sketching and shading with pencils and crayons.

    As he grew up and delved deeper into how computers are made, he became intrigued by the materials that have enabled the integration of electronic devices into computer processors. So, when it came time to select his undergraduate major, Tiwale ultimately chose materials science and engineering. He was accepted to his dream school, the Indian Institute of Technology (IIT) Bombay, one of the top engineering universities in India.

    “Computers initially used vacuum tubes as electronic switches and took up whole rooms,” said Tiwale. “Now, we have million-times-faster computers that we can carry in our pockets. To a large extent, advances in materials science made storing and processing information on tiny chips possible. This dramatic improvement in performance is one of the main reasons that I wanted to study materials science and engineering in college.”

    But his artistic side never left him. Students at IIT Bombay were encouraged to participate in extracurricular activities, and Tiwale decided he would hone his art skills. He taught himself how to use advanced graphic design software like Photoshop, and graphic design became one of his hobbies. Little did he know that his artistic foundations would prove to be instrumental in his scientific career.

    1
    A nanowire “firecracker.” The scanning electron microscope image is of zinc oxide nanowires that Tiwale and his PhD colleague grew on a graphite flake via thermal chemical vapor deposition. The University of Cambridge’s Engineering Department publicized this image in “The art of engineering: images from the frontiers of technology” annual photography competition in 2014.

    Tiwale graduated from IIT Bombay with a bachelor’s degree in metallurgical engineering and materials science, and a master’s in ceramics and composites. Then, he pursued a PhD in solid-state electronics and nanoscale science at the University of Cambridge in the United Kingdom. For his PhD research, which was under the guidance of Sir Mark Welland, Tiwale sought to develop a scalable method for making devices from zinc oxide nanowires. These one-dimensional wire-shaped structures have a diameter smaller than 100 nanometers, roughly the size of a virus. When charges are confined to a single dimension, unique electronic and optical properties emerge.

    “At the time, most of the research in the field of oxide nanostructures had been focused on growing high-quality nanowires on one substrate, sprinkling these nanowires on a device-compatible substrate, making devices one by one, and then trying to understand how the material is performing,” explained Tiwale. “But this process isn’t scalable for making complex circuits or computer chips, for example. The first thing that comes to my mind regarding scalability for any semiconductor device is lithography-based patterning.”

    The art of lithography

    A Greek word that translates to “writing on stones,” lithography is a technique for generating patterns on material surfaces (substrates) through exposure to light, electrons, ions, or other external stimuli. Lithography is the primary technique that has enabled the precision patterning of electronic device structures. For example, to make integrated circuits, a light-sensitive material called a photoresist is coated onto a thin wafer of silicon. The resist is then selectively exposed to light through a “mask” containing the geometric pattern for the required electronic circuit.

    “Photolithography is like taking a photograph,” explained Tiwale. “You take a snapshot of an entire circuit diagram and simultaneously print that onto a substrate. On the other hand, electron-beam lithography (EBL) is like drawing or sketching. You pattern one structure at a time and combine these structures to make your final circuit. To mass produce devices, you need both—the sketching-like lithography to design and optimize the structures, and the photography-like lithography to simultaneously transfer these structures onto a substrate at a fast pace.”

    Using unique zinc-based precursor (reactant) materials that are sensitive to electrons, Tiwale developed an EBL process for the direct patterning of zinc oxide nanowires at desired locations on device substrates.

    “With this process, hundreds and thousands of nanowire devices can be made simultaneously, meaning you can design circuits and more complicated structures,” said Tiwale, who used the process to make transistors (the building blocks of computer circuits) and gas sensors capable of detecting and distinguishing different vapors.

    For Tiwale, lithography is as much a science as it is an art.

    “I think of lithography as architecture at the micro or nanoscale,” said Tiwale. “Making an integrated circuit or chip is like architecting a several-story building. The physical layout of the processor architecture is the “floorplan,” and each microprocessor contains tens of layers, or floors. To make these integrated structures, you not only need an understanding of materials science but also graphic design skills. The scientific and artistic sides come together.”

    One of Tiwale’s major inspirations is Leonardo da Vinci, who had a passion for both art and science.

    “da Vinci is famously known for his artistic masterpieces like the Mona Lisa, but he also drew detailed sketches of human anatomy and aircraft blueprints,” said Tiwale. “He imagined science and technology centuries before they were materialized.”

    3
    (Left) A scanning electron microscope image of a suspended nanostructure fabricated using electron-beam lithography (EBL) and reactive-ion etching. (Right) A series of polymeric nanodots patterned during a suboptimal EBL run. As Tiwale explained, “scientific experiments do not always lead to perfect outcomes, but they can depict beautiful structures nonetheless.”

    Aligned research themes

    In 2017, toward the end of his PhD program at Cambridge, Tiwale began looking for postdoc job openings and came across a position describing a project very similar to the one he had been working on. The position was in the Electronic Nanomaterials Group of the Center for Functional Nanomaterials (CFN)—a U.S. Department of Energy (DOE) Office of Science User Facility at Brookhaven National Laboratory. In this group, CFN staff scientists Chang-Yong Nam and Aaron Stein were also using EBL to make polymer-based nanoscaffolds for oxide nanodevices. While Tiwale’s technique was limited to a single metallic precursor, Nam’s and Stein’s could be applied to different metals. Therefore, they could explore materials with a variety of properties beyond those ideal for transistors and gas sensors.

    “The position had a good overlap with my PhD research, and I’d have the chance to extend the research to different materials and applications,” said Tiwale.

    Tiwale was also attracted to the user-oriented nature of the CFN. At the University of Cambridge, he had conducted his PhD research in The Nanoscience Centre, a university-wide user facility. Here, Tiwale served as an instructor for new users of EBL and other cleanroom-based processing tools.

    “I really liked how my regular interactions with members of various departments across the university pulled me out of my narrow research focus and got me thinking about broader ideas in science,” said Tiwale. “As a worldwide user center, CFN takes this interaction to another level.”

    Postdoctoral research

    Since March 2018, Tiwale has been a postdoc in the CFN Electronic Nanomaterials Group. Initially, he focused his research on infiltration synthesis, a technique for growing inorganic materials within polymers by introducing precursors in gas form. Working in the CFN Materials Synthesis and Characterization Facility, Tiwale used this technique to produce inorganic metal oxide nanostructures. One of the applications of interest to the group is the fabrication of metal oxide nanowires, like those Tiwale was making during his PhD studies, for functional applications.

    Last year, Tiwale was the lead experimentalist on a team who used infiltration synthesis to make “hybrid” resists—those that combine organic polymer-based materials with inorganic materials like zinc, tin, and aluminum. As Tiwale explained, the microelectronics industry has been moving toward extreme-ultraviolet lithography, or EUVL, to further miniaturize device features. EUVL requires new resist materials that are sensitive to extreme ultraviolet light. The addition of inorganic elements can boost the sensitivity of organic components. Highly sensitive resists require less exposure time, translating to improved processing efficiencies. The team, led by Nam, has since been exploring hybrid resists with a variety of material compositions. In addition to exploiting x-ray characterization techniques at Brookhaven’s National Synchrotron Light Source II (NSLS-II) [below]—also a DOE Office of Science User Facility—to understand these nanocomposites, they are actively engaging with leading companies in the semiconductor industry such as Intel and Samsung and collaborating with the Center for X-ray Optics at DOE’s Lawrence Berkeley National Laboratory.

    5
    (Left to right) Ashwanth Subramanian, Ming Lu, Kim Kisslinger, Chang-Yong Nam, and Nikhil Tiwale in the CFN Electron Microscopy Facility. The team created a hybrid organic-inorganic resist through infiltration synthesis, patterned the resist via electron-beam lithography, and etched the pattern into silicon by bombarding the silicon surface with ions of sulfur hexafluoride, or SF6 (top right). The high-magnification scanning electron microscope image (inset in graph) shows high-resolution, high-aspect-ratio silicon nanostructures patterned at a pitch resolution (width of lines and the spaces between them) of 500 nanometers. As shown in the graph, after two processing cycles, the etch selectivity of the hybrid resist surpasses that of a costly resist called ZEP; after four cycles, the hybrid resist has a 40-percent-higher etch selectivity than that of silicon dioxide (SiO2).

    Tiwale is now extending infiltration synthesis to new classes of semiconducting materials with unique properties that could increase computer speed and memory capabilities. He is also making ultrathin layers—only a few nanometers thick—of metal oxides through atomic layer deposition. These ultrathin layers are generated during a sequential process in which precursors react to form the desired products. Currently, Tiwale is studying and exploring how the metal oxides can be coupled with 2-D materials to make functional devices.

    Lithography continues to be an important part of Tiwale’s research. Before Tiwale arrived at the CFN, the group had been combining EBL and block copolymer lithography to obtain specific morphologies in selected areas on a substrate. Block copolymers are a special class of materials where two or more chemically distinct sequences (“blocks”) spontaneously form ordered nanostructures of a particular morphology. By mixing together different block copolymers and directing them with EBL, Stein and CFN Electronic Nanomaterials Group Leader Kevin Yager were able to get lines and dots to coexist in pre-designated locations. Stein presented this work at a “Three-beams” conference that Tiwale attended during his PhD, spurring his interest.

    “Morphology is important because it can dictate material properties,” explained Tiwale. “Specific arrangements of different morphologies are widely applied in photonic waveguides, semiconducting lasers, and flat lenses that are enabling the integration of complex optics into smartphone cameras.”

    6
    Examples of multiple morphologies in desired locations on a single substrate.

    Collaborating with fellow postdocs in the Electronic Nanomaterials Group, Tiwale has been expanding this lithography approach to obtain a wider range of morphology types—such as holes and sheets—on the same layer. Last year, he helped with a project led by Yager in which they performed lithography multiple times to specify regions of desired morphologies on a single substrate. The team is now aiming to replace these multiple patterning steps with one step, which could make the process practically viable for fabricating device-related structures.

    “If we can simultaneously direct block copolymers to assemble in a certain way at specific locations, then we will be able to make very high-density nanopatterns with function-specific morphologies—for example, lines for circuit elements, dots and holes to interconnect device circuit layers, and sheets to construct new transistor architectures. High density means we can fit more devices in the same physical space, thus making computers faster.”

    Beyond his own research projects, Tiwale is collaborating with colleagues from his PhD days—now faculty at prominent research institutes in India—who have become CFN users. Currently, he is contributing to nanopatterning for next-generation solar cells based on hybrid perovskites—alternative materials to silicon that could provide higher efficiency—and making perovskite transistors to understand how electrical charges are transferred in these materials. He is also collaborating with University of Wisconsin–Madison users who are growing arrays of graphene nanoribbons that weave into each other to make large-area meshes. Graphene in its 2-D form is a metal-like conducting material, but graphene nanoribbons less than 10 nanometers wide show semiconducting behavior, making them promising channel materials for transistors.

    “The CFN has provided an environment for me to not only progress my own research with the help of experts and unique capabilities, but also to expand my collaborations and drive different research ideas toward applications,” said Tiwale.

    7
    Tiwale enjoys sharing research with others through various outreach activities at the CFN, including tours and open-house events.

    When Tiwale completes his postdoc next year, he would like to continue this application-oriented research and translate discoveries into practical device platforms.

    “So far, semiconductor technology has been heavily dependent on advancing a particular type of device architecture to make smaller and faster devices,” said Tiwale. “But opportunities for creating different types of nanostructuring using lithography will open up as new avenues for next-generation computing—such as quantum electronics and photonic computing—are pursued and as consumer electronics head toward more interactive display platforms. I am excited to pursue these opportunities, applying my passions of science and art.”

    See the full article here .


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

    Please help promote STEM in your local schools.

    Stem Education Coalition

    Brookhaven 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.

     
  • richardmitnick 11:06 am on December 4, 2020 Permalink | Reply
    Tags: "Exploring Blended Materials Along Compositional Gradients", , DOE’s Brookhaven National Laboratory, ,   

    From DOE’s Brookhaven National Laboratory: “Exploring Blended Materials Along Compositional Gradients” 

    From DOE’s Brookhaven National Laboratory

    November 24, 2020
    Ariana Manglaviti
    amanglaviti@bnl.gov
    (631) 344-2347

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

    A new platform for rapidly creating and characterizing blends of polymers, nanoparticles, and other materials could significantly accelerate material development.

    1
    Yale University PhD student Kristof Toth with the electrospray deposition tool he designed, built, and validated in collaboration with staff scientist Gregory Doerk of Brookhaven Lab’s Center for Functional Nanomaterials (CFN) [below]. This CFN tool allows users to blend multiple components—such as polymers, nanoparticles, and small molecules—over a range of compositions in a single sample. Next door to the CFN, at the National Synchrotron Light Source II [below], users can probe how the structure of the blended material changes across this entire composition space.

    Blending is a powerful strategy for improving the performance of electronics, coatings, separation membranes, and other functional materials. For example, high-efficiency solar cells and light-emitting diodes have been produced by optimizing mixtures of organic and inorganic components.

    However, finding the optimal blend composition to produce desired properties has traditionally been a time-consuming and inconsistent process. Scientists synthesize and characterize a large number of individual samples with different compositions one at a time, eventually compiling enough data to create a compositional “library.” An alternative approach is to synthesize a single sample with a compositional gradient so that all possible compositions can be explored at once. Existing combinatorial methods for rapidly exploring compositions have been limited in terms of the types of compatible materials, the size of compositional increments, or number of blendable components (often only two).

    2
    A schematic of the electrospray deposition tool (a), with zoomed-in (b) and aerial (c) views.

    To overcome these limitations, a team from the U.S. Department of Energy’s (DOE) Brookhaven National Laboratory, Yale University, and University of Pennsylvania recently built [AIP Review of Scientific Instruments] a first-of-its-kind automated tool for depositing films with finely controlled blend compositions made of up to three components onto single samples. Solutions of each component are loaded into syringe pumps, mixed according to a programmable “recipe,” and sprayed as tiny electrically charged droplets onto the surface of a heated base material called a substrate. By programming the flow rates of the pumps as a stage underneath the substrate changes position, users can obtain continuous gradients in composition.

    Now, the team has combined this electrospray deposition tool with the structural characterization technique of x-ray scattering. Together, these capabilities form a platform to probe how material structure changes across an entire composition space. The scientists demonstrated this platform for a thin-film blend of three polymers—chains made of molecular building blocks linked together by chemical bonds—designed to spontaneously arrange, or “self-assemble,” into nanometer-scale (billionths of a meter) patterns. Their platform and demonstration are described in a paper published today in RSC Advances, a journal of the Royal Society of Chemistry (RSC).

    “Our platform reduces the time to explore complex compositional dependencies of blended material systems from months or weeks to a few days,” said corresponding author Gregory Doerk, a staff scientist in the Electronic Nanomaterials Group at Brookhaven Lab’s Center for Functional Nanomaterials (CFN)[below].

    3
    The morphology diagram derived from the x-ray scattering data shows where in the composition space the cylinders, lamellae (vertical sheets), spheres, and disorder occur. Pure PS-PMMA block copolymer is located at the top of the triangle, and pure PMMA and PS homopolymers are at the lower left and right of the triangle, respectively. Each colored point represents a single x-ray measurement (the numbered points correspond to measurements described in detail in the paper).

    “We constructed a morphology diagram with more than 200 measurements on a single sample, which is like making 200 samples the conventional way,” said first author Kristof Toth, a PhD student in the Department of Chemical and Environmental Engineering at Yale University. “Our approach not only reduces sample preparation time but also sample-to-sample error.”

    This diagram mapped how the morphologies, or shapes, of the blended polymer system changed along a compositional gradient of 0 to 100 percent. In this case, the system contained a widely studied self-assembling polymer made of two distinct blocks (PS-b-PMMA) and this block copolymer’s individual block constituents, or homopolymers (PS and PMMA). The scientists programmed the electrospray deposition tool to consecutively create one-dimensional gradient “strips” with all block copolymer at one end and all homopolymer blend at the other end.

    To characterize the structure, the team performed grazing-incidence small-angle x-ray scattering experiments at the Complex Materials Scattering (CMS) beamline, which is operated at Brookhaven’s National Synchrotron Light Source II (NSLS-II) in partnership with the CFN. In this technique, a high-intensity x-ray beam is directed toward the surface of a sample at a very low angle. The beam reflects off the sample in a characteristic pattern, providing snapshots of nanoscale structures at different compositions along each five-millimeter-long strip. From these images, the shape, size, and ordering of these structures can be determined.

    4
    Each deposited strip is a gradient from block copolymer (C) to homopolymer blend (A+B) on a single substrate. Within each strip, the homopolymer blend is maintained at a constant PS (B) to PMMA (A) ratio.

    “The synchrotron’s high intensity x-rays allow us to take snapshots at each composition in a matter of seconds, reducing the overall time to map the morphology diagram,” said co-author Kevin Yager, leader of the CFN Electronic Nanomaterials Group.

    The x-ray scattering data revealed the emergence of highly ordered morphologies of different kinds as the blend composition changed. Normally, the block copolymers self-assemble into cylinders. However, blending in very short homopolymers resulted in well-ordered spheres (increasing amount of PS) and vertical sheets (more PMMA). The addition of these homopolymers also tripled or quadrupled the speed of the self-assembly process, depending on the ratio of PS to PMMA homopolymer. To further support their results, the scientists performed imaging studies with a scanning electron microscope at the CFN Materials Synthesis and Characterization Facility.

    5
    X-ray scattering patterns (left) with corresponding scanning electron microscope (SEM) images (middle) and morphology schematics (right) for selected numbered points in the morphology diagram. Vertical sheets occur at point 2, cylinders at point 5, and spheres at point 6. The scale bars in the SEM images indicate a length of 200 nanometers.

    Though the team focused on a self-assembling polymer system for their demonstration, the platform can be used to explore blends of a variety of materials such as polymers, nanoparticles, and small molecules. Users can also study the effects of different substrate materials, film thicknesses, x-ray beam focal spot sizes, and other processing and characterization conditions.

    “This capability to survey a broad range of compositional and processing parameters will inform the creation of complex nanostructured systems with enhanced or entirely new properties and functionalities,” said co-author Chinedum Osuji, the Eduardo D. Glandt Presidential Professor of Chemical and Biomolecular Engineering at the University of Pennsylvania.

    In the future, the scientists hope to create a second generation of the instrument that can create samples with mixtures of more than three components and which is compatible with a range of characterization methods—including in situ methods to capture morphology changes during the electrospray deposition process.

    “Our platform represents a huge advance in the amount of information you can get across a composition space,” said Doerk. “In a few days, users can work with me at the CFN and the beamline staff next door at NSLS-II to create and characterize their blended systems.”

    “In many ways, this platform complements autonomous methods developed by CFN and NSLS-II scientists to identify trends in experimental data,” added Yager. “Pairing them together has the potential to dramatically accelerate soft matter research.”

    This work was funded by the DOE Office of Science and National Science Foundation. The CFN and NSLS-II are DOE Office of Science User Facilities.

    CFN facilities are available free of charge to scientists from universities, industry, and national laboratories worldwide. If you are interested in using the new electrospray deposition tool for your research, submit a proposal. The next deadline is January 31, 2021. If you have questions about the CFN user program, please contact CFN User Program Administrator and Outreach Coordinator Grace Webster at (631) 344-3227 or gwebster@bnl.gov. For questions about using CFN facilities or partnering with CFN scientists, please contact CFN Assistant Director for Strategic Partnerships Priscilla Antunez at (631) 344-6186 or pantunez@bnl.gov.

    See the full article here .


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

    Please help promote STEM in your local schools.

    Stem Education Coalition

    Brookhaven 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.

     
  • richardmitnick 1:35 pm on November 23, 2020 Permalink | Reply
    Tags: "Quantum X-ray microscope in development", , , DOE’s Brookhaven National Laboratory, ,   

    From DOE’s Brookhaven National Laboratory: “Quantum X-ray microscope in development” 

    From DOE’s Brookhaven National Laboratory

    November 23, 2020

    Researchers at the National Synchrotron Light Source II will use the quantum properties of x-rays to “ghost image” biomolecules.

    1
    An artist’s interpretation of ghost imaging. In this research technique, scientists split an x-ray beam (represented by the thick pink line) into two streams of entangled photons (thinner pink lines). Only one of these streams of photons passes through the scientific sample (represented by the clear circle), but both gather information. By splitting the beam, the sample being studied is only exposed to a fraction of the x-ray dose. Credit: Brookhaven National Laboratory.

    3

    Scientists at the U.S. Department of Energy’s (DOE) Brookhaven National Laboratory have begun building a quantum-enhanced X-ray microscope at the National Synchrotron Light Source II (NSLS-II) [below]. This groundbreaking microscope, supported by the Biological and Environmental Research progam at DOE’s Office of Science, will enable researchers to image biomolecules like never before.

    NSLS-II is a DOE Office of Science User Facility where researchers use powerful X-rays to ‘see’ the structural, chemical, and electronic makeup of materials down to the atomic scale. The facility’s ultrabright light already enables discoveries in biology, helping researchers uncover the structures of proteins to inform drug design for a variety of diseases—to name just one example.

    Now, by tapping into the quantum properties of X-rays, researchers at NSLS-II will be able to image more sensitive biomolecules without sacrificing resolution. While the high penetration power of X-rays enables superior resolution for imaging studies, this powerful light can also damage certain biological samples, such as plant cells, viruses, and bacteria. Low-dose X-ray studies can preserve these samples, but the imaging resolution is reduced.

    “If we are successful in building a quantum-enhanced X-ray microscope, we will be able to image biomolecules with very high resolution and a very low dose of X-rays,” said Sean McSweeney, manager of the structural biology program at NSLS-II.

    The quantum-enhanced X-ray microscope at NSLS-II will achieve this remarkable combination of capabilities through an experimental technique called ghost imaging. Compared to typical X-ray imaging techniques, which send a single beam of photons (particles of light) through a sample and onto a detector, ghost imaging requires the X-ray beam be split into two streams of entangled photons—only one of which passes through the sample, but both gather information.

    “One stream goes through the sample and is collected by a detector that records the photons with good time resolution, while the other stream of photons encodes the exact direction in which the photons propagate,” said Andrei Fluerasu, lead beamline scientist at NSLS-II’s Coherent Hard X-ray Scattering (CHX) beamline, where the microscope will be developed. “It sounds like magic. But with mathematical calculations, we’ll be able to correlate the information from the two beams.”

    By splitting the beam, the sample being studied is only exposed to a fraction of the X-ray dose. And since the photons that do not pass through the sample are correlated with the photons that do, the resolution of a full-dose X-ray beam is maintained.

    Ghost imaging techniques have already been successfully developed using photons of visible light, but translating this technique to X-ray light will be a major scientific achievement.

    The quantum-enhanced X-ray microscope at Brookhaven Lab is being developed at NSLS-II’s CHX beamline, which was chosen for its ability to manipulate the coherence of the X-ray source, enabling scientists to tune the ghost imaging experiments as needed. CHX’s existing setup was also flexible enough to accommodate the addition of new and advanced equipment, such as a beam splitter and a new detector. NSLS-II will collaborate with physicists at Brookhaven Lab and Stony Brook University on the integration of these complex instruments.

    Stony Brook

    “These measurements will require imaging detectors with the best possible timing resolution,” said Brookhaven physicist Andrei Nomerotski, “and this is something we are already using for high energy physics experiments, quantum information science projects like quantum astrometry, and fast optical imaging.”

    The quantum-enhanced X-ray microscope project team will also collaborate with Brookhaven’s Computational Science Initiative (CSI) on data analysis. The Lab’s biology department is partnering with NSLS-II to design experiments that exploit the advanced capabilities of this microscope.

    “Our Biology colleagues at Brookhaven are excited to bring us complex problems to solve using this new instrument,” McSweeney said. “With involvement from Physics, Biology, and CSI, we have put an excellent team together for this groundbreaking project.”

    “The strong working relationship between Biology and NSLS-II scientists brings together real-world scientific problems and advanced capabilities, delivering cutting-edge solutions for problems relative to the DOE mission,” said John Shanklin, Chair of the Lab’s biology department. “It’s a win-win situation.”

    The team plans to gradually integrate new functionalities into the CHX beamline over the next two to three years. The project will be complete upon demonstrating ghost imaging of micron-sized objects with resolution below 10 nanometers, which is targeted for 2023.

    See the full article here .


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

    Please help promote STEM in your local schools.

    Stem Education Coalition

    Brookhaven 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.

     
  • richardmitnick 1:33 pm on November 9, 2020 Permalink | Reply
    Tags: "New 'Genomic' Method Reveals Atomic Arrangements of Battery Material", , , DOE’s Brookhaven National Laboratory,   

    From DOE’s Brookhaven National Laboratory: “New ‘Genomic’ Method Reveals Atomic Arrangements of Battery Material” 

    From DOE’s Brookhaven National Laboratory

    November 9, 2020
    Karen McNulty Walsh
    kmcnulty@bnl.gov
    (631) 344-8350

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

    1
    The low-temperature structure of NVPF [Na3V2(PO4)2F3] solved in this work. Calculations from Lawrence Berkeley National Laboratory suggest that the sodium atoms (white) can move most easily in the planes between the cation sites of vanadium (teal) and phosphorus (mauve) atoms during battery use.

    Scientists at the U.S. Department of Energy’s (DOE) Brookhaven National Laboratory, Stony Brook University (SBU), the Materials Project at DOE’s Lawrence Berkeley National Laboratory (Berkeley Lab), the University of California, Berkeley, and European collaborators have developed a new way to decipher the atomic-level structure of materials based on data gleaned from ground-up powder samples. They describe their approach and demonstrate its ability to solve the structure of a material that shows promise for shuttling ions through sodium-ion batteries in a paper just published in the journal Chemistry of Materials.

    “Our approach combines experiment, theory, and modern computational tools to provide the high-quality structural data needed to understand important functional materials, even when only powder samples are available,” said corresponding author Peter Khalifah, who holds a joint appointment at Brookhaven Lab and SBU.

    The technique is in some ways a form of reverse engineering. Instead of solving the structure directly from the experimental data measured on the powder sample—a problem too complex to be possible for many materials—it uses computer algorithms to build and evaluate all the plausible structures of a material. By analyzing the “genome” associated with a material in this way, it can be possible to find the correct structure even when this structure is so complex that conventional methods for structure solution fail.

    2
    Brookhaven Lab/Stony Brook University chemist Peter Khalifah.

    Battery cathode freeze-frame

    For the study described in the paper, x-ray powder diffraction experiments were performed at the ALBA synchrotron in Barcelona, Spain, by European collaborators Matteo Bianchini and Francois Fauth, part of a team led by Christian Masquelier.

    ALBA Synchrotron via Lightsources.org

    ALBA Synchrotron interior via Mariusmm
    https://commons.wikimedia.org/wiki/User:Mariusmm

    Scientists used that facility’s bright x-ray beams to study the atomic arrangement of a sodium-ion battery cathode material known as NVPF at a variety of temperatures ranging from room temperature down to the very low cryogenic temperatures at which atmospheric gases liquefy. This work is necessary because the disorder in the room temperature structure of NVPF disappears when it is cooled to cryogenic temperatures. And while batteries operate near room temperature, deciphering the material’s cryogenic structure is still critically important because only this disorder-free, low-temperature structure can give scientists a clear understanding of the true chemical bonding that is present at room temperature. This chemical bonding environment strongly influences how ions move through the structure at room temperature and thus affects NVPF’s performance as a battery material.

    “The bonding environment around sodium atoms—how many neighbors each one has—is essentially the same at low temperature as it is at room temperature,” Khalifah explained, but trying to capture those details at room temperature is like trying to get kids to sit still for a photo. “Everything gets blurred because the ions are moving around too quickly to allow a picture to be taken.” For this reason, some of the bonding environments inferred from the room temperature data are not correct. In contrast, cryogenic temperatures freeze the motion of sodium ions to provide a true picture of the local environment where the sodium ions sit when they’re not moving around.

    “As the material is cooled, twenty-four neighboring sodium ions are each forced to choose one of two possible sites, and their lowest-energy preferred ‘ordering’ pattern can be resolved,” Khalifah said.

    A preliminary analysis of the powder x-ray diffraction data by Bianchini indicated that the pattern of ordering is very complex. For materials with such complex orderings, it is not typically possible to solve their three-dimensional atomic structure using powder diffraction data.

    “Powder diffraction data gets flattened to one dimension, so a lot of information is lost,” Khalifah said.

    But materials made of many different types of elements, as is the case for NVPF—which is built from atoms of sodium, vanadium, phosphorus, fluorine, and oxygen with an overall chemical formula of Na3V2(PO4)2F3—are too hard to grow into larger crystals for more conventional 3-D x-ray crystallography.

    So, the Brookhaven group collaborated with John Dagdelen and other researchers at Lawrence Berkeley National Laboratory to develop a new “genomic” approach that can solve very complex structures using only powder diffraction data. The collaborative work was carried out within the Materials Project, a DOE-funded research team led by Kristin Persson at LBNL that is developing innovative computational approaches for accelerating the discovery of novel functional materials.

    “Instead of using the powder diffraction data to directly solve the structure, we took an alternate approach,” Khalifah said. “We asked, ‘what are all the plausible arrangements of sodium ions in the structure,’ and then we tested each of those in an automated fashion to compare it with the experimental data to figure out what the structure was.”

    The NVPF structure is one of the most complex ever solved for a material using only powder diffraction data.

    “We couldn’t have done this science without modern computational tools—the enumeration methods used to generate the chemically plausible structures and the sophisticated automated scripts for refining those structures that utilized the pymatgen (Python Materials Genomics) software library,” Khalifah said.

    Zeroing in on the structure

    Based on the available structural knowledge for NVPF and on a set of basic chemical rules for bonding, there are more than half a million plausible ordering patterns for the sodium atoms in NVPF. Even after applying computational algorithms to identify equivalent structures generated through different ordering choices, nearly 3,000 unique possible orderings remained.

    “These 3,000 trial structures are more than can reasonably be tested by hand, but their correctness could be evaluated by a single computer working non-stop for about two days,” Khalifah said.

    The correctness of each trial structure was evaluated using software to predict what its powder x-ray diffraction pattern would look like, and then comparing the calculated results to the experimentally measured diffraction data, work done by Stony Brook Ph.D. student Gerard Mattei. If the difference between the predicted and observed diffraction patterns is relatively small, the software can optimize any trial structure by tweaking the positions of its constituent atoms to improve the agreement between the calculated and observed patterns.

    But even after such tweaking, almost 2,500 of the optimized structures could be used to fit the experimental diffraction data well.

    “We weren’t expecting to get so many good fits,” Khalifah said. “So, we had a second challenge of determining which one of those many possible structures was correct by looking at which one had the correct symmetry.”

    Crystallographic symmetry provides the rules that constrain how atoms can be arranged in a material, so fully understanding the symmetry of a structure is necessary to correctly describe it, Khalifah noted.

    The team had generated each of the trial structures with a specific set of symmetry constraints. And although it was very challenging to determine the true symmetry of any one trial structure after its optimization, a comparison of all 2,500 optimized structures allowed the researchers to determine which symmetry elements were needed to correctly describe the true structure of NVPF.

    The ability to compare results across many trials allows a higher degree of confidence in the final solution and is an additional advantage that the novel method used in this work has over traditional approaches. Furthermore, theoretical calculations done by LBNL researchers John Dagdelen and Alex Ganose indicated that the final solution is stable against distortions, confirming the validity of this result.

    The solved structure revealed that there is much greater diversity in the bonding of sodium atoms than had been previously recognized.

    “From the room temperature data, it misleadingly appeared that all sodium atoms were bonded to either six or seven neighboring atoms,” Khalifah said. “In contrast, the low temperature data clearly indicated that some sodium atoms have as few as four neighbors. One result of this is that the sodium atoms with fewer neighbors are much less locked into place and are thus expected to have an easier time moving throughout the structure—a property that is essential for battery function.”

    The authors believe this novel approach should be broadly applicable for solving the complex structures that commonly occur in battery materials when ions are removed during charging. This is especially relevant in materials used in sodium- and potassium-ion batteries, which are being developed as lower-cost and more-abundant alternatives to lithium-ion battery materials. This research thus should play an important role in unlocking the potential of earth-abundant materials that can be used to scale up energy storage capabilities to meet societal needs such as grid-scale storage.

    This research 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

    Brookhaven 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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