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  • richardmitnick 12:54 pm on May 10, 2019 Permalink | Reply
    Tags: , “Belle II will accumulate more than 50 times the data sample of the original Belle experiment at KEK”, “We are developing the data-distribution software working not only with Belle II colleagues but also with colleagues at CERN., “We store an entire copy of the Belle II data and we have the computing resources to process that data and make it available to collaborators around the world”, , Belle II detector, Benefitting from our own experience at the RHIC & ATLAS Computing Center, BNL, Brookhaven’s magnet division constructed 43 custom-designed corrector magnets., , , , Physicists and engineers in the Laboratory’s Superconducting Magnet Division made contributions essential to upgrading the KEK accelerator helping to transform it into SuperKEKB., Physicists will search for signs of “new physics”—something that cannot be explained by the particles and forces already included in the Standard Model., , SuperKEKB accelerator, SuperKEKB collides electrons with their antimatter counterparts known as positrons, The corrector magnets are installed on each side of the Belle II detector   

    From Brookhaven National Lab: “Brookhaven Lab and the Belle II Experiment” 

    From Brookhaven National Lab

    May 7, 2019
    Karen McNulty Walsh
    kmcnulty@bnl.gov

    Tracking particle smashups and detector conditions from half a world away, scientists seek answers to big physics mysteries.

    1
    SuperKEKB accelerator and Belle II detector at the interaction region.(Credit: Belle II/KEK)

    If you think keeping track of the photos on your mobile phone is a challenge, imagine how daunting the job would be if your camera were taking thousands of photos every second. That’s the task faced by particle physicists working on the Belle II experiment at Japan’s SuperKEKB particle accelerator, which started its first physics run in late March. Belle II physicists will sift through “snapshots” of millions of subatomic smashups per day—as well as data on the conditions of the “camera” at the time of each collision—to seek answers to some of the biggest questions in physics.

    A key part of the experiment is taking place half a world away, using computing resources and expertise at the U.S. Department of Energy’s Brookhaven National Laboratory, the lead laboratory for U.S. collaborators on Belle II.

    “We store an entire copy of the Belle II data, and we have the computing resources to process that data and make it available to collaborators around the world,” said Benedikt Hegner, a physicist in Brookhaven Lab’s Computational Sciences Initiative. To date, Brookhaven’s Scientific Data and Computing Center (SDCC) has handled up to 95 percent of the experiment’s entire computing workload—reconstructing particles from simulated events prior to the experiment’s startup, and since late March, from live collision events. SDCC will continue that role for the experiment’s first three years, thereafter maintaining some 30 percent of the data-transfer and storage responsibility while transitioning the rest to other Belle II member nations that have powerful GRID computing capabilities.

    “We are developing the data-distribution software, working not only with Belle II colleagues but also with colleagues at CERN, the European laboratory for particle physics research, learning from their experience managing datasets from the Large Hadron Collider (LHC)—as well as our own experience at the RHIC & ATLAS Computing Center,” Hegner said.

    2
    Benedikt Hegner in the Scientific Data and Computing Center at Brookhaven Lab, which stores and processes Belle II data and makes it available to collaborators around the world.

    Brookhaven also hosts Belle II’s “conditions database”—an archive of the detector’s conditions at the time of each recorded collision. This database tracks millions of variables—for example, the detector’s level of electronic noise, millimeter-scale movements of the detector due to the strong magnetic field, and variations in electronic response due to small temperature changes—all of which need to be properly taken into account to make sense of Belle II’s measurements.

    “This is the first time a particle physics experiment’s conditions database is being hosted at a distant location,” Hegner noted. Tracking the conditions helps calibrate the detector and even feeds input to the “trigger” systems that decide which collisions to record. “If we’re having trouble with our system, Belle II will eventually see that during data collection. So, the reliability of our services is essential,” Hegner said.

    But Brookhaven’s involvement in Belle II goes beyond cataloging collisions and crunching the numbers. Physicists and engineers in the Laboratory’s Superconducting Magnet Division made contributions essential to upgrading the KEK accelerator, helping to transform it into SuperKEKB, and members of Brookhaven Lab’s physics department are looking forward to analyzing Belle II data and being part of the upgraded facility’s discoveries.

    Improved magnets, more collisions, “new physics”?

    Like its predecessor, SuperKEKB collides electrons with their antimatter counterparts, known as positrons. To keep collision rates high, these beams must be tightly focused. But the magnetic fields guiding the particles in one beam can have unwanted effects in the adjacent beam, causing the particles to spread. To fine-tune the fields of the accelerator magnets and counteract these adjacent-beam effects, Brookhaven’s magnet division constructed 43 custom-designed corrector magnets. These corrector magnets are installed on each side of the Belle II detector, making adjustments to both the incoming and outgoing beams to maintain high beam intensity, or “luminosity.” High luminosity results in higher collision rates, so physicists at Brookhaven and around the world will have more data to analyze.

    4
    Corrector magnets: Leak field cancel coil being wound by Brookhaven Lab magnet division technician Thomas Van Winckel.

    “Belle II will accumulate more than 50 times the data sample of the original Belle experiment at KEK,” said Brookhaven physicist David Jaffe, who is coordinating Brookhaven Lab scientists’ involvement in the project.

    By scouring reconstructed images of the particles emerging from these electron-positron collisions, physicists will search for signs of “new physics”—something that cannot be explained by the particles and forces already included in the Standard Model, the world’s reigning (and well-tested) theory of particle physics.

    One particular area of interest is the decay of beauty and charm mesons—particles made of two quarks, one of which is a heavy “beauty” or “charm” quark. These “heavy flavor” mesons are created in abundance in electron-positron collisions at the SuperKEKB accelerator.

    “SuperKEKB is called a ‘B factory’ because it is optimized for the production of beauty mesons. It also produces an abundance of charm mesons,” Jaffe said. “While many physicists on Belle II will be investigating the behavior of beauty mesons, the Brookhaven team will be exploiting the huge sample of charm mesons to look for possible discoveries.”

    For example, if heavy flavor mesons measured by Belle II decay (transform into other particles) differently than predicted by the Standard Model, such a discrepancy would be an indication that some new, previously undiscovered particle might be taking part in the action.

    Evidence of new particles might help account for the mysterious dark matter that makes up some 27 percent of the universe, or offer clues about dark energy, which accounts for another 68 percent (with the remaining 5 percent made of the ordinary matter we see around us). Such a discovery might also help explain why today’s universe is made of matter rather than a mix of matter and antimatter, even though scientists believe both were created in equal amounts at the very beginning of time.

    To grasp how shocking this matter-antimatter asymmetry is, think of the common laundry experience of losing a random sock in the dryer. But imagine if every time you did the laundry—even a billion loads, each with a billion pairs of socks labeled “left” and “right”—you always ended up with a single unpaired left sock and never a lone right sock. That’s what it’s like for physicists trying to understand why the universe ended up with only matter. There must be some difference in the way matter and antimatter behave to explain this anomaly.

    There is evidence that matter and antimatter behave differently from several well-known experiments studying meson decays. These include a Nobel Prize-winning experiment at Brookhaven’s Alternating Gradient Synchrotron, which studied the decay of mesons containing a strange quark in the 1960s. More recently, several experiments studying beauty meson decays at other B factories—the original Belle at KEK, the BaBar experiment at the SLAC National Accelerator Laboratory in the U.S., and the LHCb experiment at CERN—observed similar asymmetries. But thus far, the matter-antimatter asymmetry observed in beauty and strange mesons follows the pattern predicted by the Standard Model, and is not sufficient to explain the matter-antimatter asymmetry of the universe.

    LHCb also recently observed a smaller level of matter-antimatter asymmetry in charm meson decays for the first time. It is unclear if this new observation is consistent with the Standard Model or due to new particles that preferentially interact with charm quarks. Additional measurements are needed to solve this mystery.

    5
    Physicist David Jaffe is coordinating Brookhaven Lab’s contributions to Belle II.

    “What we’ll do at Belle II is like many, many trips to the laundromat where we carefully launder our `charmed’ socks and use different methods to dry them. We’ll use our observations from these different loads of charmed laundry to map out what happens in charm meson decays to higher precision than ever before,” explained Jaffe. “Then we’ll compare those observations to our expectations from the Standard Model to see if we’ve found evidence for new particles.”

    The Belle II experiment, Jaffe noted, complements LHCb. “Belle II has a different range of features that enable contrasting studies of the charm mesons,” he said. “We are starting to accumulate large data samples to help us make the precision measurements we need to resolve these questions. Once we’ve confirmed the technical capabilities of the experiment, we will move on to data analysis and the possibility of discovery.”

    See the full article here .


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

    Please help promote STEM in your local schools.

    Stem Education Coalition

    BNL Campus


    BNL Center for Functional Nanomaterials

    BNL NSLS-II


    BNL NSLS II

    BNL RHIC Campus

    BNL/RHIC Star Detector

    BNL RHIC PHENIX

    One of ten national laboratories overseen and primarily funded by the Office of Science of the U.S. Department of Energy (DOE), Brookhaven National Laboratory conducts research in the physical, biomedical, and environmental sciences, as well as in energy technologies and national security. Brookhaven Lab also builds and operates major scientific facilities available to university, industry and government researchers. The Laboratory’s almost 3,000 scientists, engineers, and support staff are joined each year by more than 5,000 visiting researchers from around the world. Brookhaven is operated and managed for DOE’s Office of Science by Brookhaven Science Associates, a limited-liability company founded by Stony Brook University, the largest academic user of Laboratory facilities, and Battelle, a nonprofit, applied science and technology organization.
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  • richardmitnick 12:22 pm on May 10, 2019 Permalink | Reply
    Tags: , , BNL, , , ,   

    From Brookhaven National Lab: “New Approach for Solving Protein Structures from Tiny Crystals” 

    From Brookhaven National Lab

    May 3, 2019
    Karen McNulty Walsh
    kmcnulty@bnl.gov
    (631) 344-8350

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

    Technique opens door for studies of countless hard-to-crystallize proteins involved in health and disease.

    1
    Wuxian Shi, Martin Fuchs, Sean McSweeney, Babak Andi, and Qun Liu at the FMX beamline at Brookhaven Lab’s National Synchrotron Light Source II [see below], which was used to determine a protein structure from thousands of tiny crystals.

    Using x-rays to reveal the atomic-scale 3-D structures of proteins has led to countless advances in understanding how these molecules work in bacteria, viruses, plants, and humans—and has guided the development of precision drugs to combat diseases such as cancer and AIDS. But many proteins can’t be grown into crystals large enough for their atomic arrangements to be deciphered. To tackle this challenge, scientists at the U.S. Department of Energy’s (DOE) Brookhaven National Laboratory and colleagues at Columbia University have developed a new approach for solving protein structures from tiny crystals.

    The method relies on unique sample-handling, signal-extraction, and data-assembly approaches, and a beamline capable of focusing intense x-rays at Brookhaven’s National Synchrotron Light Source II (NSLS-II)—a DOE Office of Science user facility—to a millionth-of-a-meter spot, about one-fiftieth the width of a human hair.

    “Our technique really opens the door to dealing with microcrystals that have been previously inaccessible, including difficult-to-crystallize cell-surface receptors and other membrane proteins, flexible proteins, and many complex human proteins,” said Brookhaven Lab scientist Qun Liu, the corresponding author on the study, which was published on May 3 in IUCrJ, a journal of the International Union of Crystallography.

    Deciphering protein structures

    Protein crystallography has been a dominant method for solving protein structures since 1958, improving over time as x-ray sources have grown more powerful, allowing more precise structure determinations. To determine a protein structure, scientists measure how x-rays like those generated at NSLS-II diffract, or bounce off, the atoms in an ordered crystalline lattice consisting of many copies of the same protein molecule all arrayed the same way. The diffraction pattern conveys information about where the atoms are located. But it’s not sufficient.

    2
    A cartoon representing the structure of a well-studied plant protein that served as a test case for the newly developed microcrystallography technique. Magenta mesh patterns surrounding sulfur atoms intrinsic to the protein (yellow spheres) indicate the anomalous signals that were extracted using low-energy x-ray diffraction of thousands of crystals measuring less than 10 millionths of a meter, the size of a bacterium.

    “Only the amplitudes of diffracted x-ray ‘waves’ are recorded on the detector, but not their phases (the timing between waves),” said Liu. “Both are required to reconstruct a 3-D structure. This is the so-called crystallographic phase problem.”

    Crystallographers have solved this problem by collecting phase data from a different kind of scattering, known as anomalous scattering. Anomalous scattering occurs when atoms heavier than a protein’s main components of carbon, hydrogen, and nitrogen absorb and re-emit some of the x-rays. This happens when the x-ray energy is close to the energy those heavy atoms like to absorb. Scientists sometimes artificially insert heavy atoms such as selenium or platinum into the protein for this purpose. But sulfur atoms, which appear naturally throughout protein molecules, can also produce such signals, albeit weaker. Even though these anomalous signals are weak, a big crystal usually has enough copies of the protein with enough sulfur atoms to make them measurable. That gives scientists the phase information needed to pinpoint the location of the sulfur atoms and translate the diffraction patterns into a full 3-D structure.

    “Once you know the sulfur positions, you can calculate the phases for the other protein atoms because the relationship between the sulfur and the other atoms is fixed,” said Liu.

    But tiny crystals, by definition, don’t have that many copies of the protein of interest. So instead of looking for diffraction and phase information from repeat copies of a protein in a single large crystal, the Brookhaven/Columbia team developed a way to take measurements from many tiny crystals, and then assemble the collective data.

    Tiny crystals, big results

    To handle the tiny crystals, the team developed sample grids patterned with micro-sized wells. After pouring solvent containing the microcrystals over these well-mount grids, the scientists removed the solvent and froze the crystals that were trapped on the grids.

    3
    Micro-patterned sample grids for manipulation of microcrystals.

    “We still have a challenge, though, because we can’t see where the tiny crystals are on our grid,” said Liu. “To find out, we used microdiffraction at NSLS-II’s Frontier Microfocusing Macromolecular Crystallography (FMX) beamline to survey the whole grid. Scanning line by line, we can find where those crystals are hidden.”

    As Martin Fuchs, the lead beamline scientist at FMX, explained, “The FMX beamline can focus the full intensity of the x-ray beam down to a size of one micron, or millionth of a meter. We can finely control the beam size to match it to the size of the crystals—five microns in the case of the current experiment. These capabilities are crucial to obtain the best signal,” he said.

    Wuxian Shi, another FMX beamline scientist, noted that “the data collected in the grid survey contains information about the crystals’ location. In addition, we can also see how well each crystal diffracts, which allows us to pick only the best crystals for data collection.”

    The scientists were then able to maneuver the sample holder to place each mapped out microcrystal of interest back in the center of the precision x-ray beam for data collection.

    They used the lowest energy available at the beamline—tuned to approach as closely as possible sulfur atoms’ absorption energy—and collected anomalous scattering data.

    “Most crystallographic beamlines could not reach the sulfur absorption edge for optimized anomalous signals,” said co-author Wayne Hendrickson of Columbia University. “Fortunately, NSLS-II is a world-leading synchrotron light source providing bright x-rays covering a broad spectrum of x-ray energy. And even though our energy level was slightly above the ideal absorption energy for sulfur, it generated the anomalous signals we needed.”

    But the scientists still had some work to do to extract those important signals and assemble the data from many tiny crystals.

    “We are actually getting thousands of pieces of data,” said Liu. “We used about 1400 microcrystals, each with its own data set. We have to put all the data from those microcrystals together.”

    4
    Scientists used a five-micron x-ray beam at the FMX beamline at NSLS-II to scan the entire grid and locate the tiny invisible crystals. Then a heat map (green) was used to guide the selection of positions for diffraction data acquisition.

    They also had to weed out data from crystals that were damaged by the intense x-rays or had slight variations in atomic arrangements.

    “A single microcrystal does not diffract x-rays sufficiently for structure solution prior to being damaged by the x-rays,” said Sean McSweeney, deputy photon division director and program manager of the Structural Biology Program at NSLS-II. “This is particularly true with crystals of only a few microns, the size of about a bacterial cell. We needed a way to account for that damage and crystal structure variability so it wouldn’t skew our results.”

    They accomplished these goals with a sophisticated multi-step workflow process that sifted through the data, discarded outliers that might have been caused by radiation damage or incompatible crystals, and ultimately extracted the anomalous scattering signals.

    “This is a critical step,” said Liu. “We developed a computing procedure to assure that only compatible data were merged in a way to align the individual microcrystals from diffraction patterns. That gave us the required signal-to-noise ratios for structure determination.”

    Applying the technique

    This technique can be used to determine the structure of any protein that has proven hard to crystallize to a large size. These include cell-surface receptors that allow cells of advanced lifeforms such as animals and plants to sense and respond to the environment around them by releasing hormones, transmitting nerve signals, or secreting compounds associated with cell growth and immunity.

    “To adapt to the environment through evolution, these proteins are malleable and have lots of non-uniform modifications,” said Liu. “It’s hard to get a lot of repeat copies in a crystal because they don’t pack well.”

    In humans, receptors are common targets for drugs, so having knowledge of their varied structures could help guide the development of new, more targeted pharmaceuticals.

    But the technique is not restricted to just small crystals.

    “The method we developed can handle small protein crystals, but it can also be used for any size protein crystals, any time you need to combine data from more than one sample,” Liu said.

    This research was supported in part by Brookhaven National Laboratory’s “Laboratory Directed Research and Development” program and the National Institutes of Health (NIH) grant GM107462. The NSLS-II at Brookhaven Lab is a DOE Office of Science user facility (supported by DE-SC0012704), with beamline FMX supported primarily by the National Institute of Health, National Institute of General Medical Sciences (NIGMS) through a Biomedical Technology Research Resource P41 grant (P41GM111244), and by the DOE Office of Science.

    See the full article here .


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

    Please help promote STEM in your local schools.

    Stem Education Coalition

    BNL Campus


    BNL Center for Functional Nanomaterials

    BNL NSLS-II


    BNL NSLS II

    BNL RHIC Campus

    BNL/RHIC Star Detector

    BNL RHIC PHENIX

    One of ten national laboratories overseen and primarily funded by the Office of Science of the U.S. Department of Energy (DOE), Brookhaven National Laboratory conducts research in the physical, biomedical, and environmental sciences, as well as in energy technologies and national security. Brookhaven Lab also builds and operates major scientific facilities available to university, industry and government researchers. The Laboratory’s almost 3,000 scientists, engineers, and support staff are joined each year by more than 5,000 visiting researchers from around the world. Brookhaven is operated and managed for DOE’s Office of Science by Brookhaven Science Associates, a limited-liability company founded by Stony Brook University, the largest academic user of Laboratory facilities, and Battelle, a nonprofit, applied science and technology organization.
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  • richardmitnick 9:03 am on May 4, 2019 Permalink | Reply
    Tags: , , BNL, Lisa Miller, ,   

    From Brookhaven National Lab: Women n STEM- “Meet NSLS-II’s Lisa Miller” 

    From Brookhaven National Lab

    May 1, 2019
    Stephanie Kossman
    skossman@bnl.gov

    1
    As the manager of NSLS-II’s USCEO office, Lisa Miller can usually be found traveling around the facility’s experimental floor on trike—the most fun (and the safest) way to quickly get around NSLS-II’s half-mile ring.

    When Lisa Miller isn’t managing outreach efforts at the National Synchrotron Light Source II (NSLS-II) [image s below], she’s using the facility’s ultrabright x-ray light to study neurological protein-misfolding diseases, such as Alzheimer’s disease.

    Today, Miller is the manager of NSLS-II’s user services, communications, education, and outreach (USCEO) office, but she first came to the U.S. Department of Energy’s (DOE) Brookhaven National Laboratory 25 years ago as a doctoral student at NSLS, the predecessor of NSLS-II—a DOE Office of Science User Facility at Brookhaven.

    “My thesis advisor came to NSLS all the time,” Miller said. “He would send a team of four students and we would spend a lot of time collecting each other’s data. I always got the night shift.”

    Having developed a passion for scientific collaboration and helping others collect their data, Miller decided to come back to NSLS for a postdoctoral research project—building an infrared beamline (experimental station) for biological research.

    2
    When Lisa Miller isn’t managing outreach efforts at NSLS-II, she’s using the facility’s ultrabright x-ray light to study neurological protein-misfolding diseases, such as Alzheimer’s disease.

    “And I’ve been here ever since,” she said. “After my postdoc, I ran two infrared beamlines at NSLS for 15 years.”

    Growing up, Miller and her three younger sisters were always encouraged to follow whatever career path they wanted. “Being a girl didn’t matter,” she said. “My dad taught us to drive a tractor, change the oil in the car, and fix the leaky sink. We got tools for our birthdays.”

    Of the four girls, Miller was the only one to become a scientist. “I always knew I liked science, but I never imagined working at a synchrotron light source,” she said. “I wanted to get a faculty job in a four-year undergraduate institution and teach. Research was a secondary thing to me. But in my early years at NSLS, I had such supportive mentors. All of the beamline scientists were so willing to help me succeed that, after a year, I had no desire to look for a faculty position.”

    During her time at NSLS and NSLS-II, Miller has been researching “protein-misfolding” diseases like Alzheimer’s disease, in which normal proteins in the brain clump together to form “plaques” and cause neurodegeneration—the death of brain cells.

    “We used the x-ray and infrared microscopes at NSLS to show that these plaques are loaded with metal ions like copper and zinc,” Miller said. “These metals are nutritionally essential, but they’re not supposed to be in the plaques. We’ve hypothesized that the metals can cause toxic reactions in the brain, leading to cell death. Now we are trying to figure out how and why this happens.”

    To move the field forward, Miller is developing new research methods that use the advanced capabilities of NSLS-II.

    “NSLS-II is a huge improvement for my research, especially in terms of the spatial resolution it provides,” she said. “Now we have these really tiny x-ray beams that enable us to image individual parts of the cells, including cell membranes, in order to understand how the metal ions are transported into the cells and damage them. The suite of imaging beamlines that we have here at NSLS-II enables us to study the problem from the level of the brain tissue all the way down to individual molecules in the cells.”

    Throughout her years of research, Miller retained her interest in science education. In 2001, she was asked to lead NSLS’s information and outreach office. Then, once NSLS-II was established, she became the facility’s first manager of USCEO.

    “Continuing my research is a really important part of my career, but that includes sharing my passion for science through teaching and outreach,” she said. As an adjunct associate professor in chemistry and biomedical engineering at Stony Brook University, Miller mentors doctoral students in synchrotron science. “Their generation will figure out the next cool things that synchrotrons can do.”

    Miller’s outreach efforts extend to the visiting researcher, or “user,” program that she oversees at NSLS-II.

    “My goal is for the users at NSLS-II to have a “Disneyland” user experience—to be able to do top-notch research, from conceiving the idea to doing the experiments and publishing the work, and having us support that. It’s more than just the photons; it’s everything from the registration process to comfortable accommodations and good coffee.”

    From the visiting researchers to the beamline scientists and support staff, Miller says having the chance to interact with so many different people is her favorite part of working at the light source.

    “We have a tremendous variety of personalities and a melting pot of people from all over the world,” she said. “The synchrotron community is a really welcoming and collaborative environment to be in.”

    As much as Miller likes working at NSLS-II, she stresses the importance of a work-life balance. Outside of “the office,” you can find Miller on backpacking trips around the country and the world. She’s hiked to the high points of 49 states, backpacked over 600 miles of the Appalachian Trail, and climbed Mount Kilimanjaro in Africa.

    Miller earned a Ph.D. in biophysics from Albert Einstein College of Medicine in 1995 and an M.S. in Chemistry from Georgetown University in 1992.

    See the full article here .


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

    Please help promote STEM in your local schools.

    Stem Education Coalition

    BNL Campus


    BNL Center for Functional Nanomaterials

    BNL NSLS-II


    BNL NSLS II

    BNL RHIC Campus

    BNL/RHIC Star Detector

    BNL RHIC PHENIX

    One of ten national laboratories overseen and primarily funded by the Office of Science of the U.S. Department of Energy (DOE), Brookhaven National Laboratory conducts research in the physical, biomedical, and environmental sciences, as well as in energy technologies and national security. Brookhaven Lab also builds and operates major scientific facilities available to university, industry and government researchers. The Laboratory’s almost 3,000 scientists, engineers, and support staff are joined each year by more than 5,000 visiting researchers from around the world. Brookhaven is operated and managed for DOE’s Office of Science by Brookhaven Science Associates, a limited-liability company founded by Stony Brook University, the largest academic user of Laboratory facilities, and Battelle, a nonprofit, applied science and technology organization.
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  • richardmitnick 2:29 pm on April 26, 2019 Permalink | Reply
    Tags: "New Lens System for Brighter Sharper Diffraction Images", "The team used a photocathode gun that generates the electrons through a process called photoemission”, , “We made the sample by depositing the gold atoms on a several nanometer thick carbon film using a technique called thermal evaporation”, BNL, Brookhaven’s Accelerator Test Facility, , Electron beam-related research techniques, , , , The researchers used two groups of four quadrupole magnets to tune the electron beam., Ultra-fast electron diffraction imaging   

    From Brookhaven National Lab: “New Lens System for Brighter, Sharper Diffraction Images” 

    From Brookhaven National Lab

    April 25, 2019

    Cara Laasch
    laasch@bnl.gov
    (631) 344-8458

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

    Researchers from Brookhaven Lab designed, implemented, and applied a new and improved focusing system for electron diffraction measurements.

    1
    Mikhail Fedurin, Timur Shaftan, Victor Smalyuk, Xi Yang, Junjie Li, Lewis Doom, Lihua Yu, and Yimei Zhu are the Brookhaven team of scientists that realized and demonstrated the new lens system for as ultra-fast electron diffraction imaging.

    To design and improve energy storage materials, smart devices, and many more technologies, researchers need to understand their hidden structure and chemistry. Advanced research techniques, such as ultra-fast electron diffraction imaging can reveal that information. Now, a group of researchers from the U.S. Department of Energy’s (DOE) Brookhaven National Laboratory have developed a new and improved version of electron diffraction at Brookhaven’s Accelerator Test Facility (ATF)—a DOE Office of Science User Facility that offers advanced and unique experimental instrumentation for studying particle acceleration to researchers from all around the world. The researchers published their findings in Scientific Reports, an open-access journal by Nature Research.

    Advancing a research technique such as ultra-fast electron diffraction will help future generations of materials scientists to investigate materials and chemical reactions with new precision. Many interesting changes in materials happen extremely quickly and in small spaces, so improved research techniques are necessary to study them for future applications. This new and improved version of electron diffraction offers a stepping stone for improving various electron beam-related research techniques and existing instrumentation.

    “We implemented our new focusing system for electron beams and demonstrated that we can improve the resolution significantly when compared to the conventional solenoid technique,” said Xi Yang, author of the study and an accelerator physicist at the National Synchrotron Light Source II (NSLS-II) [see below], a DOE Office of Science User Facility at Brookhaven Lab. “The resolution mainly depends on the properties of light – or in our case – of the electron beam. This is universal for all imaging techniques, including light microscopy and x-ray imaging. However, it is much more challenging to focus the charged electrons to a near-parallel pencil-like beam at the sample than it would be with light, because electrons are negatively charged and therefore repulse one another. This is called the space charge effect. By using our new setup, we were able to overcome the space charge effect and obtain diffraction data that is three times brighter and two times sharper; it’s a major leap in resolution.”

    2
    The colorful images are four different electron diffraction measurements at ATF. The left column shows diffraction patterns of the sample using the newly developed quadrupoles, while the right column shows diffraction patterns without the new lens system. In the left column the rings of the pattern are sharper, rounder and turn red, which means that the overall resolution of the measurement is higher.

    Every electron diffraction setup uses an electron beam that is focused on the sample so that the electrons bounce off the atoms in the sample and travel further to the detector behind the sample. The electrons create a so-called diffraction pattern, which can be translated into the structural makeup of the materials at the nanoscale. The advantage of using electrons to image this inner structure of materials is that the so called diffraction limit of electrons is very low, which means scientists can resolve smaller details in the structure compared to other diffraction methods.

    A diverse team of researchers was needed to improve such a complex research method. The Brookhaven Lab team consisted of electron beam experts from the NSLS-II, electron accelerator experts from ATF, and materials science experts from the condensed matter physics & materials science (CMPMS) department.

    “This advance would not have been possible without the combination of all our expertise across Brookhaven Lab. At NSLS-II, we have expertise on how to handle the electron beam. The ATF group brought the expertise and capabilities of the electron gun and laser technologies – both of which were needed to create the electron beam in the first place. And the CMPMS group has the sample expertise and, of course, drives the application needs. This is a unique synergy and, together, we were able to show how the resolution of the technique can be improved drastically,” said Li Hua Yu, NSLS-II senior accelerator physicist and co-author of the study.

    To achieve its improved resolution, the team developed a different method of focusing the electron beam. Instead of using a conventional approach that involves solenoid magnets, the researchers used two groups of four quadrupole magnets to tune the electron beam. Compared to solenoid magnets, which act as just one lens to shape the beam, the quadrupole magnets work like a specialized lens system for the electrons, and they gave the scientists far more flexibility to tune and shape the beam according to the needs of their experiment.

    “Our lens system can provide a wide range of tunability of the beam. We can optimize the most important parameters such as beam size, or charge density, and beam divergence based on the experimental conditions, and therefore provide the best beam quality for the scientific needs,” said Yang.

    The team can even adjust the parameters on-the-fly with online optimization tools and correct any nonuniformities of the beam shape; however, to make this measurement possible, the team needed the excellent electron beam that ATF provides. ATF has an electron gun that generates an extremely bright and ultrashort electron beam, which offers the best conditions for electron diffraction.

    “The team used a photocathode gun that generates the electrons through a process called photoemission,” said Mikhail Fedurin, an accelerator physicist at ATF. “We shoot an ultrashort laser pulse into a copper cathode, and when the pulse hits the cathode a cloud of electrons forms over the copper. We pull the electrons away using an electric field and then accelerate them. The amount of electrons in one of these pulses and our capability to accelerate them to specific energies make our system attractive for material science research – particularly for ultrafast electron diffraction.”

    The focusing system together with the ATF electron beam is very sensitive, so the researchers can measure the influences of Earth’ magnetic field on the electron beam.

    “In general, electrons are always influenced by magnetic fields—this is how we steer them in particle accelerators in the first place; however, the effect of Earth’s magnetic field is not negligible for the low-energy beam we used in this experiment,” said Victor Smalyuk, NSLS-II accelerator physics group leader and co-author of the study. “The beam deviated from the desired trajectory, which created difficulties during the initial starting phase, so we had to correct for this effect.”

    Beyond the high brightness of the electron beam and the high precision of the focusing system, the team also needed the right sample to make these measurements. The CMPMS group provided the team with a polycrystalline gold film to fully explore the newly designed lens system and to put it to the test.

    “We made the sample by depositing the gold atoms on a several nanometer thick carbon film using a technique called thermal evaporation,” said Junjie Li, a physicist in the CMPMS department. “We evaporated gold particles so that they condense on the carbon film and form tiny, isolated nanoparticles that slowly merge together and form the polycrystalline film.”

    This film was essential for the measurements because it has randomly oriented crystals that merge together. Therefore, the inner structure of the sample is not uniform, but consists of many differently oriented areas, which means that the diffraction pattern mainly depends on the electron beam qualities. This gives the scientists the best ground to really test their lens system, to tune the beam, and to see the impact of their tuning directly in the quality of the diffraction measurement.

    “We initially set out to improve electron diffraction for scientific studies of materials, but we also found that this technique can help us characterize our electron beam. In fact, diffraction is very sensitive to the electron beam parameters, so we can use the diffraction pattern of a known sample to measure our beam parameters precisely and directly, which is usually not that easy,” said Yang.

    The team intends to pursue further improvements, and they already have plans to develop another setup for ultra-fast electron microscopy to directly visualize a biological sample.

    “We hope to achieve ultrafast single-shot electron beam imaging at some point and maybe even make molecular movies, which isn’t possible with our current electron beam imaging setup,” said Yang.

    This research was supported by Laboratory Directed Research and Development funding and by DOE’s Office of Science through its support of the ATF.

    See the full article here .


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    Please help promote STEM in your local schools.

    Stem Education Coalition

    BNL Campus


    BNL Center for Functional Nanomaterials

    BNL NSLS-II


    BNL NSLS II

    BNL RHIC Campus

    BNL/RHIC Star Detector

    BNL RHIC PHENIX

    One of ten national laboratories overseen and primarily funded by the Office of Science of the U.S. Department of Energy (DOE), Brookhaven National Laboratory conducts research in the physical, biomedical, and environmental sciences, as well as in energy technologies and national security. Brookhaven Lab also builds and operates major scientific facilities available to university, industry and government researchers. The Laboratory’s almost 3,000 scientists, engineers, and support staff are joined each year by more than 5,000 visiting researchers from around the world. Brookhaven is operated and managed for DOE’s Office of Science by Brookhaven Science Associates, a limited-liability company founded by Stony Brook University, the largest academic user of Laboratory facilities, and Battelle, a nonprofit, applied science and technology organization.
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  • richardmitnick 2:03 pm on April 26, 2019 Permalink | Reply
    Tags: "Building a Printing Press for New Quantum Materials", “We realized that building a robot that can enable the design synthesis and testing of quantum materials is extremely well-matched to the skills and expertise of scientists at the CFN.”, BNL, CFN-Center for Functional Nanomaterials, Exotic electronic magnetic and optical properties emerge at such small (quantum) size scales., , , Once high-quality 2-D flakes from different crystals have been located and their properties characterized they can be assembled in the desired order to create the layered structures., Quantum Material Press or QPress, Structures obtained by stacking single atomic layers (“flakes”) peeled from different parent bulk crystals are of interest   

    From Brookhaven National Lab: “Building a Printing Press for New Quantum Materials” 

    From Brookhaven National Lab

    April 22, 2019
    Ariana Tantillo
    atantillo@bnl.gov

    Scientists at Brookhaven Lab’s Center for Functional Nanomaterials are developing an automated system to synthesize entirely new materials made from stacked atomically thin two-dimensional sheets and to characterize their exotic quantum properties.

    BNL Center for Functional Nanomaterials

    1
    Scientists at Brookhaven Lab’s Center for Functional Nanomaterials are building a robotic system to enable the design, synthesis, and testing of quantum materials, which exhibit unique properties. From left to right: Gregory Doerk, Jerzy Sadowski, Kevin Yager, Young Jae Shin, and Aaron Stein.

    Checking out a stack of books from the library is as simple as searching the library’s catalog and using unique call numbers to pull each book from their shelf locations. Using a similar principle, scientists at the Center for Functional Nanomaterials (CFN)—a U.S. Department of Energy (DOE) Office of Science User Facility at Brookhaven National Laboratory—are teaming with Harvard University and the Massachusetts Institute of Technology (MIT) to create a first-of-its-kind automated system to catalog atomically thin two-dimensional (2-D) materials and stack them into layered structures. Called the Quantum Material Press, or QPress, this system will accelerate the discovery of next-generation materials for the emerging field of quantum information science (QIS).

    Structures obtained by stacking single atomic layers (“flakes”) peeled from different parent bulk crystals are of interest because of the exotic electronic, magnetic, and optical properties that emerge at such small (quantum) size scales. However, flake exfoliation is currently a manual process that yields a variety of flake sizes, shapes, orientations, and number of layers. Scientists use optical microscopes at high magnification to manually hunt through thousands of flakes to find the desired ones, and this search can sometimes take days or even a week, and is prone to human error.

    Once high-quality 2-D flakes from different crystals have been located and their properties characterized, they can be assembled in the desired order to create the layered structures. Stacking is very time-intensive, often taking longer than a month to assemble a single layered structure. To determine whether the generated structures are optimal for QIS applications—ranging from computing and encryption to sensing and communications—scientists then need to characterize the structures’ properties.

    “In talking to our university collaborators at Harvard and MIT who synthesize and study these layered heterostructures, we learned that while bits of automation exist—such as software to locate the flakes and joysticks to manipulate the flakes—there is no fully automated solution,” said CFN Director Charles Black, the administrative lead on the QPress project.

    The idea for the QPress was conceived in early 2018 by Professor Amir Yacoby of the Department of Physics at Harvard. The concept was then refined through a collaboration between Yacoby; Black and Kevin Yager, leader of the CFN Electronic Nanomaterials Group; Philip Kim, also of Harvard’s Department of Physics; and Pablo Jarillo-Herrero and Joseph Checkelsky, both of the Department of Physics at MIT.

    According to Black, the unique CFN role was clear: “We realized that building a robot that can enable the design, synthesis, and testing of quantum materials is extremely well-matched to the skills and expertise of scientists at the CFN. As a user facility, CFN is meant to be a resource for the scientific community, and QIS is one of our growth areas for which we’re expanding our capabilities, scientific programs, and staff.”

    Graphene sparks 2-D materials research

    The interest in 2-D materials dates back to 2004, when scientists at the University of Manchester isolated the world’s first 2-D material, graphene—a single layer of carbon atoms. They used a surprisingly basic technique in which they placed a piece of graphite (the core material of pencils) on Scotch tape, repeatedly folding the tape in half and peeling it apart to extract ever-thinner flakes. Then, they rubbed the tape on a flat surface to transfer the flakes. Under an optical microscope, the one-atom-thick flakes can be located by their reflectivity, appearing as very faint spots. Recognized with a Nobel Prize in 2010, the discovery of graphene and its unusual properties—including its remarkable mechanical strength and electrical and thermal conductivity—has prompted scientists to explore other 2-D materials.

    Many labs continue to use this laborious approach to make and find 2-D flakes. While the approach has enabled scientists to perform various measurements on graphene, hundreds of other crystals—including magnets, superconductors, and semiconductors—can be exfoliated in the same way as graphite. Moreover, different 2-D flakes can be stacked to build materials that have never existed before. Scientists have very recently discovered that the properties of these stacked structures depend not only on the order of the layers but also on the relative angle between the atoms in the layers. For example, a material can be tuned from a metallic to an insulating state simply by controlling this angle. Given the wide variety of samples that scientists would like to explore and the error-prone and time-consuming nature of manual synthesis methods, automated approaches are greatly needed.

    “Ultimately, we would like to develop a robot that delivers a stacked structure based on the 2-D flake sequences and crystal orientations that scientists select through a web interface to the machine,” said Black. “If successful, the QPress would enable scientists to spend their time and energy studying materials, rather than making them.”

    A modular approach

    In September 2018, further development of the QPress was awarded funding by the DOE, with a two-part approach. One award was for QPress hardware development at Brookhaven, led by Black; Yager; CFN scientists Gregory Doerk, Aaron Stein, and Jerzy Sadowski; and CFN scientific associate Young Jae Shin. The other award was for a coordinated research project led by Yacoby, Kim, Jarillo-Herrero, and Checkelsky. The Harvard and MIT physicists will use the QPress to study exotic forms of superconductivity—the ability of certain materials to conduct electricity without energy loss at very low temperatures—that exist at the interface between a superconductor and magnet. Some scientists believe that such exotic states of matter are key to advancing quantum computing, which is expected to surpass the capabilities of even today’s most powerful supercomputing.

    3
    A photo of the prototype exfoliator. The robotic system transfers peeled 2-D flakes from the parent crystal to a substrate. The exfoliator allows scientists to control stamping pressure, pressing time, number of repeated presses, angle of pressing, and lateral force applied during transfer, for improved repeatability.

    A fully integrated automated machine consisting of an exfoliator, a cataloger, a library, a stacker, and a characterizer is expected in three years. However, these modules will come online in stages to enable the use of QPress early on.

    The team has already made some progress. They built a prototype exfoliator that mimics the action of a human peeling flakes from a graphite crystal. The exfoliator presses a polymer stamp into a bulk parent crystal and transfers the exfoliated flakes by pressing them onto a substrate. In their first set of experiments, the team investigated how changing various parameters—stamping pressure, pressing time, number of repeated presses, angle of pressing, and lateral force applied during transfer—impact the process.

    “One of the advantages of using a robot is that, unlike a human, it reproduces the same motions every time, and we can optimize these motions to generate lots of very thin large flakes,” explained Yager. “Thus, the exfoliator will improve both the quality and quantity of 2-D flakes peeled from parent crystals by refining the speed, precision, and repeatability of the process.”

    In collaboration with Stony Brook University assistant professor Minh Hoai Nguyen of the Department of Computer Science and PhD student Boyu Wang of the Computer Vision Lab, the scientists are also building a flake cataloger. Through image-analysis software, the cataloger scans a substrate and records the locations of exfoliated flakes and their properties.

    “The flakes that scientists are interested in are thin and thus faint, so manual visual inspection is a laborious and error-prone process,” said Nguyen. “We are using state-of-the-art computer vision and deep learning techniques to develop software that can automate this process with higher accuracy.”

    4
    A schematic showing the workflow for cataloging flake locations and properties. Image grids of exfoliated samples are automatically analyzed, with each flake tracked individually so that scientists can locate any desired flake on a sample.

    “Our collaborators have said that a system capable of mapping their sample of flakes and showing them where the “good” flakes are located—as determined by parameters they define—would be immensely helpful for them,” said Yager. “We now have this capability and would like to put it to use.”

    Eventually, the team plans to store a large set of different catalogued flakes on shelves, similar to books in a library. Scientists could then access this materials library to select the flakes they want to use, and the QPress would retrieve them.

    According to Black, the biggest challenge will be the construction of the stacker—the module that retrieves samples from the library, “drives” to the locations where the selected flakes reside, and picks the flakes up and places them in a repetitive process to build stacks according to the assembly instructions that scientists program into the machine. Ultimately, the scientists would like the stacker to assemble the layered structures not only faster but also more accurately than manual methods.

    5
    The QPress will have five modules when completed: an exfoliator, a cataloger, a materials library, a stacker, and a characterizer/fabricator.

    The final module of the robot will be a material characterizer, which will provide real-time feedback throughout the entire synthesis process. For example, the characterizer will identify the crystal structure and orientation of exfoliated flakes and layered structures through low-energy electron diffraction (LEED)—a technique in which a beam of low-energy electrons is directed toward the surface of a sample to produce a diffraction pattern characteristic of the surface geometry.

    “There are many steps to delivering a fully automated solution,” said Black. “We intend to implement QPress capabilities as they become available to maximize benefit to the QIS community.”

    See the full article here .


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

    Please help promote STEM in your local schools.

    Stem Education Coalition

    BNL Campus


    BNL Center for Functional Nanomaterials

    BNL NSLS-II


    BNL NSLS II

    BNL RHIC Campus

    BNL/RHIC Star Detector

    BNL RHIC PHENIX

    One of ten national laboratories overseen and primarily funded by the Office of Science of the U.S. Department of Energy (DOE), Brookhaven National Laboratory conducts research in the physical, biomedical, and environmental sciences, as well as in energy technologies and national security. Brookhaven Lab also builds and operates major scientific facilities available to university, industry and government researchers. The Laboratory’s almost 3,000 scientists, engineers, and support staff are joined each year by more than 5,000 visiting researchers from around the world. Brookhaven is operated and managed for DOE’s Office of Science by Brookhaven Science Associates, a limited-liability company founded by Stony Brook University, the largest academic user of Laboratory facilities, and Battelle, a nonprofit, applied science and technology organization.
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  • richardmitnick 10:48 am on April 22, 2019 Permalink | Reply
    Tags: "Optimizing Network Software to Advance Scientific Discovery", , , BNL, CSI-The computer is installed at Brookhaven's Scientific Data and Computing Center, DiRAC-Distributed Research Using Advanced Computing, Intel's high-speed communication network to accelerate application codes for particle physics and machine learning,   

    From Brookhaven National Lab: “Optimizing Network Software to Advance Scientific Discovery” 

    From Brookhaven National Lab

    April 16, 2019
    Ariana Tantillo
    atantillo@bnl.gov

    A team of computer scientists, physicists, and software engineers optimized software for Intel’s high-speed communication network to accelerate application codes for particle physics and machine learning.

    1
    Brookhaven Lab collaborated with Columbia University, University of Edinburgh, and Intel to optimize the performance of a 144-node parallel computer built from Intel’s Xeon Phi processors and Omni-Path high-speed communication network. The computer is installed at Brookhaven’s Scientific Data and Computing Center, as seen above with technology engineer Costin Caramarcu.

    High-performance computing (HPC)—the use of supercomputers and parallel processing techniques to solve large computational problems—is of great use in the scientific community. For example, scientists at the U.S. Department of Energy’s (DOE) Brookhaven National Laboratory rely on HPC to analyze the data they collect at the large-scale experimental facilities on site and to model complex processes that would be too expensive or impossible to demonstrate experimentally.

    Modern science applications, such as simulating particle interactions, often require a combination of aggregated computing power, high-speed networks for data transfer, large amounts of memory, and high-capacity storage capabilities. Advances in HPC hardware and software are needed to meet these requirements. Computer and computational scientists and mathematicians in Brookhaven Lab’s Computational Science Initiative (CSI) are collaborating with physicists, biologists, and other domain scientists to understand their data analysis needs and provide solutions to accelerate the scientific discovery process.

    An HPC industry leader

    2
    An image of the Xeon Phi Knights Landing processor die. A die is a pattern on a wafer of semiconducting material that contains the electronic circuitry to perform a particular function. Credit: Intel.

    For decades, Intel Corporation has been one of the leaders in developing HPC technologies. In 2016, the company released the Intel® Xeon PhiTM processors (formerly code-named “Knights Landing”), its second-generation HPC architecture that integrates many processing units (cores) per chip. The same year, Intel released the Intel® Omni-Path Architecture high-speed communication network. In order for the 5,000 to 100,000 individual computers, or nodes, in modern supercomputers to work together to solve a problem, they must be able to quickly communicate with each other while minimizing network delays.

    Soon after these releases, Brookhaven Lab and RIKEN, Japan’s largest comprehensive research institution, pooled their resources to purchase a small 144-node parallel computer built from Xeon Phi processors and two independent network connections, or rails, using Intel’s Omni-Path Architecture.

    The computer was installed at Brookhaven Lab’s Scientific Data and Computing Center, which is part of CSI.

    With the installation completed, physicist Chulwoo Jung and CSI computational scientist Meifeng Lin of Brookhaven Lab; theoretical physicist Christoph Lehner, a joint appointee at Brookhaven Lab and the University of Regensburg in Germany; Norman Christ, the Ephraim Gildor Professor of Computational Theoretical Physics at Columbia University; and theoretical particle physicist Peter Boyle of the University of Edinburgh worked in close collaboration with software engineers at Intel to optimize the network software for two science applications: particle physics and machine learning.

    “CSI had been very interested in the Intel Omni-Path Architecture since it was announced in 2015,” said Lin. “The expertise of Intel engineers was critical to implementing the software optimizations that allowed us to fully take advantage of this high-performance communication network for our specific application needs.”

    Network requirements for scientific applications

    For many scientific applications, running one rank (a value that distinguishes one process from another) or possibly a few ranks per node on a parallel computer is much more efficient than running several ranks per node. Each rank typically executes as an independent process that communicates with the other ranks by using a standard protocol known as Message Passing Interface (MPI).

    4
    A schematic of the lattice for quantum chromodynamics calculations. The intersection points on the grid represent quark values, while the lines between them represent gluon values.

    For example, physicists seeking to understand how the early universe formed run complex numerical simulations of particle interactions based on the theory of quantum chromodynamics (QCD). This theory explains how elementary particles called quarks and gluons interact to form the particles we directly observe, such as protons and neutrons. Physicists model these interactions by using supercomputers that represent the three dimensions of space and the dimension of time in a four-dimensional (4D) lattice of equally spaced points, similar to that of a crystal. The lattice is split into smaller identical sub-volumes. For lattice QCD calculations, data need to be exchanged at the boundaries between the different sub-volumes. If there are multiple ranks per node, each rank hosts a different 4D sub-volume. Thus, splitting up the sub-volumes creates more boundaries where data need to be exchanged and therefore unnecessary data transfers that slow down the calculations.

    Software optimizations to advance science

    To optimize the network software for such a computationally intensive scientific application, the team focused on enhancing the speed of a single rank.

    “We made the code for a single MPI rank run faster so that a proliferation of MPI ranks would not be needed to handle the large communication load present for each node,” explained Christ.

    The software within the MPI rank exploits the threaded parallelism available on Xeon Phi nodes. Threaded parallelism refers to the simultaneous execution of multiple processes, or threads, that follow the same instructions while sharing some computing resources. With the optimized software, the team was able to create multiple communication channels on a single rank and to drive these channels using different threads.

    5
    Two-dimensional illustration of threaded parallelism. Key: green lines separate physical compute nodes; black lines separate MPI ranks; red lines are the communication contexts, with the arrows denoting communication between nodes or memory copy within a node via the Intel Omni-Path hardware.

    The MPI software was now set up for the scientific applications to run more quickly and to take full advantage of the Intel Omni-Path communications hardware. But after implementing the software, the team members encountered another challenge: in each run, a few nodes would inevitably communicate slowly and hold the others back.

    They traced this problem to the way that Linux—the operating system used by the majority of HPC platforms—manages memory. In its default mode, Linux divides memory into small chunks called pages. By reconfiguring Linux to use large (“huge”) memory pages, they resolved the issue. Increasing the page size means that fewer pages are needed to map the virtual address space that an application uses. As a result, memory can be accessed much more quickly.

    With the software enhancements, the team members analyzed the performance of the Intel Omni-Path Architecture and Intel Xeon Phi processor compute nodes installed on Intel’s dual-rail “Diamond” cluster and the Distributed Research Using Advanced Computing (DiRAC) single-rail cluster in the United Kingdom.

    DiRAC is the UK’s integrated supercomputing facility for theoretical modelling and HPC-based research in particle physics, astronomy and cosmology.

    For their analysis, they used two different classes of scientific applications: particle physics and machine learning. For both application codes, they achieved near-wirespeed performance—the theoretical maximum rate of data transfer. This improvement represents an increase in network performance that is between four and ten times that of the original codes.

    “Because of the close collaboration between Brookhaven, Edinburgh, and Intel, these optimizations were made available worldwide in a new version of the Intel Omni-Path MPI implementation and a best-practice protocol to configure Linux memory management,” said Christ. “The factor of five speedup in the execution of the physics code on the Xeon Phi computer at Brookhaven Lab—and on the University of Edinburgh’s new, even larger 800-node Hewlett Packard Enterprise “hypercube” computer—is now being put to good use in ongoing studies of fundamental questions in particle physics.”

    See the full article here .


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

    Please help promote STEM in your local schools.

    Stem Education Coalition

    BNL Campus


    BNL Center for Functional Nanomaterials

    BNL NSLS-II


    BNL NSLS II

    BNL RHIC Campus

    BNL/RHIC Star Detector

    BNL RHIC PHENIX

    One of ten national laboratories overseen and primarily funded by the Office of Science of the U.S. Department of Energy (DOE), Brookhaven National Laboratory conducts research in the physical, biomedical, and environmental sciences, as well as in energy technologies and national security. Brookhaven Lab also builds and operates major scientific facilities available to university, industry and government researchers. The Laboratory’s almost 3,000 scientists, engineers, and support staff are joined each year by more than 5,000 visiting researchers from around the world. Brookhaven is operated and managed for DOE’s Office of Science by Brookhaven Science Associates, a limited-liability company founded by Stony Brook University, the largest academic user of Laboratory facilities, and Battelle, a nonprofit, applied science and technology organization.
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  • richardmitnick 3:39 pm on April 11, 2019 Permalink | Reply
    Tags: “Our quantum memories operate at room temperature., BNL, BNL Scientific Data and Computing Center, DOE ESnet, Northeast Quantum Systems Center, Putting U.S. quantum networking research on the international map, , quantum entanglement is limited by decoherence, , The entanglement sources are portable and can be easily mounted in standard data center computer server racks that are connected to regular fiber distribution panels., This makes it natural to expand the test to principles of quantum repeaters which are the technological key to achieving quantum communication over hundreds of kilometers.”, Unlike digital transmissions in communication networks, Viable quantum repeaters will allow Figueroa and his team to scale up their ongoing experiments within “local-area” quantum networks to a distributed or “wide-area” version   

    From Stoney Brook University – SUNY and BNL: “Research Team Builds Quantum Network with Long-Distance Entanglement” 

    Brookhaven National Lab

    Stoney Brook bloc

    From Stoney Brook University – SUNY

    April 8, 2019
    Charity Plata
    cplata@bnl.gov

    Scientists from Stony Brook University, the U.S. Department of Energy’s Brookhaven National Laboratory, and DOE’s Energy Sciences Network (ESnet) are collaborating on an experiment that puts U.S. quantum networking research on the international map.

    Researchers, including Stony Brook’s Eden Figueroa, have built a quantum network testbed that connects several buildings on the Brookhaven Lab campus using unique portable quantum entanglement sources and an existing DOE ESnet communications fiber network—a significant step in building a large-scale quantum network that can transmit information over long distances.

    1
    Stony Brook’s Eden Figueroa describes the inner workings of the quantum network hardware at Brookhaven National Laboratory as Robinson Pino, acting director of Computational Science Research and Partnerships (SciDAC) Division overseen by DOE’s Advanced Scientific Computing Research program office, looks on.

    “In quantum mechanics, the physical properties of entangled particles remain associated, even when separated by vast distances. Thus, when measurements are performed on one side, it also affects the other,” said Kerstin Kleese van Dam, director of Brookhaven Lab’s Computational Science Initiative (CSI). “To date, this work has been successfully demonstrated with entangled photons separated by approximately 11 miles. This is one of the largest quantum entanglement distribution networks in the world, and the longest-distance entanglement experiment in the United States.”

    This quantum networking testbed project includes staff from CSI and Brookhaven’s Instrumentation Division and Physics Department, as well as faculty and students from Stony Brook University. The project also is part of the Northeast Quantum Systems Center. One distinct aspect of the team’s work that sets it apart from other quantum networks being run in China and Europe—both long-committed to quantum information science pursuits—is that the entanglement sources are portable and can be easily mounted in standard data center computer server racks that are connected to regular fiber distribution panels.

    The team successfully installed a portable quantum-entangled photon source in a server rack housed within the BNL Scientific Data and Computing Center, where the Lab’s central networking hub is located. With this connectivity, entangled photons now can be distributed to every building on the Lab’s campus using existing Brookhaven and ESnet fiber infrastructure. ESnet’s fibers have been introduced in paths between buildings to enable the distribution and study of entanglement over increasingly longer distances. The portable entanglement sources also are compatible with existing quantum memories, atom-filled glass cells that can store quantum information. Normally kept at super-cold temperatures, these cells can be stimulated using lasers to control the atomic states within them.

    In work sponsored by DOE’s Small Business Innovation Research program (SBIR), the Brookhaven-Stony Brook-ESnet testbed features portable quantum memories that can operate at room temperature. Such quantum memories, engineered for quantum networking on a large scale, have been a longtime “pet project” for Eden Figueroa, a joint appointee with Brookhaven’s CSI and Instrumentation Division and a Stony Brook University professor who leads its Quantum Information Technology group. He serves as lead investigator of the quantum networking testbed project.

    “The demonstration aims to combine entanglement with compatible atomic quantum memories,” Figueroa said. “Our quantum memories have the advantage of operating at room temperature rather than requiring subfreezing cold. This makes it natural to expand the test to principles of quantum repeaters, which are the technological key to achieving quantum communication over hundreds of kilometers.”

    Quantum networks send light pulses (photons) through the fiber, which requires the light to be periodically amplified as it travels through the lines. However, unlike digital transmissions in communication networks, quantum entanglement is limited by decoherence, where entangled photons, for example, revert to classical states because interactions with the environment cause them to lose the ability to remain entangled. This limits these fragile quantum states from being sent over large distances.

    Viable quantum repeaters will allow Figueroa and his team to scale up their ongoing experiments within “local-area” quantum networks to a distributed, or “wide-area,” version. In anticipation of this, the team is constructing the necessary optical connections to link Brookhaven Lab’s quantum network to ones that already exist at Stony Brook and Yale universities.

    “Realizing the quantum network with entangled photon sources mounted in server racks, portable quantum memories, and operable repeaters will mark the first real quantum communication network in the world that truly connects quantum computing processors and memories using photonic quantum entanglement,” Figueroa said. “It will mark a sea change in communications that can impact the world.”

    Funding for this quantum networking testbed project has been provided by SBIR, the Empire State Development Corporation, and Brookhaven Lab’s Laboratory Directed Research and Development program.

    See the full article here .

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

    Please help promote STEM in your local schools.

    Stem Education Coalition

    Stoney Brook campus

    Stony Brook University-SUNY’s reach extends from its 1,039-acre campus on Long Island’s North Shore–encompassing the main academic areas, an 8,300-seat stadium and sports complex and Stony Brook Medicine–to Stony Brook Manhattan, a Research and Development Park, four business incubators including one at Calverton, New York, and the Stony Brook Southampton campus on Long Island’s East End. Stony Brook also co-manages Brookhaven National Laboratory, joining Princeton, the University of Chicago, Stanford, and the University of California on the list of major institutions involved in a research collaboration with a national lab.

    And Stony Brook is still growing. To the students, the scholars, the health professionals, the entrepreneurs and all the valued members who make up the vibrant Stony Brook community, this is a not only a great local and national university, but one that is making an impact on a global scale.

     
  • richardmitnick 1:35 pm on April 5, 2019 Permalink | Reply
    Tags: BNL, , GISAXS-grazing-incidence small-angle x-ray scattering, NSLS-II synchrotron, Polymer self-assembly, Samantha Nowak,   

    From Brookhaven National Lab: Women in STEM- “Samantha Nowak: From CFN User to CFN Postdoc” 

    From Brookhaven National Lab

    April 5, 2019
    Ariana Tantillo
    atantillo@bnl.gov

    The chemist first came to Brookhaven Lab in 2017 as a graduate student user of the Center for Functional Nanomaterials (CFN) [below] and has since returned to do postdoctoral research in polymer self-assembly

    1
    Polymer chemist Samantha Nowak recently joined Brookhaven Lab’s Center for Functional Nanomaterials as a postdoctoral researcher studying polymer self-assembly. Here, she holds silicon wafers containing block copolymer thin films. In front of her is a plasma etch tool, which she uses to remove the domains of one of the “blocks,” or polymers, in the block copolymer. This removal is part of a process that helps Nowak better see the nanoscale self-assembled patterns (using a scanning electron microscope) formed by the block copolymer.

    When Samantha Nowak was growing up, her grandmother would complain about how she could not get her nail polish off. At the time, pure acetone—the solvent that dissolves nail polish—was not widely available. Nowak’s grandfather, a polymer chemist, would bring the “magic” nail polish remover home from his lab, explaining how solubility works. Nowak also vividly remembers her grandfather dropping metal salts into solution as she watched them rapidly crystallize to form interesting structures.

    Despite her interest in science, Nowak was set on being a lawyer up until the end of high school, when her honors chemistry teacher told her about The College of New Jersey’s forensic chemistry program that her daughter was enrolled in.

    3

    Nowak, a big fan of the television series Law & Order: Special Victims Unit, figured a career in forensic chemistry would allow her to combine her dual interests in science and law. But after declaring chemistry in her first semester at the College of New Jersey, Nowak decided that forensic chemistry was not for her. She decided to continue the general chemistry track, receiving her bachelor’s degree in 2014, with an interdisciplinary concentration in law and society.

    After graduating, Nowak entered a PhD program in chemistry at the University of Maryland (UMD), College Park, where she joined the Sita Research Group and began synthesizing and studying a new class of self-assembling materials called sugar-polyolefin conjugates.

    Self-assembly refers to the ability of certain molecules to spontaneously organize into ordered structures—such as spheres, cylinders, and lamellae (sheets)—as they try to achieve their lowest-energy state.

    “In general, block copolymer self-assembly relies on a chemical incompatibility between two different types of polymers, or “blocks,” linked together by chemical bonds,” explained Nowak. “In my PhD group, we were trying to overcome some of the limitations of block copolymer self-assembly—including the difficulty in obtaining very small feature sizes—by switching out one of the blocks with a sugar. For the other block, we used a low-molecular-weight polyolefin, which is a polymer made out of hydrogen and carbon (hydrocarbon). An extremely high incompatibility exists between the hydrophilic (water-loving) sugar and hydrophobic (water-hating) polyolefin, and the sugar molecule is extremely small with respect to the size of a typical block in a block copolymer. Because of these characteristics, there is a higher mobility that enables the reorganization of the polymer chains into multiple self-assembled structures with incredibly small feature sizes, as small as three nanometers.”

    3
    An illustration of the three-dimensional gyroid structure. This geometric configuration is found in butterfly wings and elsewhere in nature.

    For example, the sugar-polyolefin conjugates can self-assemble into stable “gyroids”—infinitely connecting structures with a minimal surface area containing no straight lines—that are lightweight yet extremely strong. These rare and complex nanostructures would be difficult to obtain and stabilize within traditional block copolymer thin films, especially those as thin as needed for electronic and optical devices. But if scientists can access gyroids and other structures with unique geometries (and thus properties), new applications may be enabled.

    Aligned research themes

    In Nowak’s third year, advisor and principal investigator Lawrence Sita contacted Kevin Yager—group leader of Electronic Nanomaterials at the Center for Functional Nanomaterials (CFN), a U.S. Department of Energy (DOE) Office of Science User Facility at Brookhaven National Laboratory. Sita thought his group’s research on the sugar-polyolefin conjugates could progress even further with Yager’s expertise and the x-ray scattering capabilities available at Brookhaven Lab’s National Synchrotron Light Source II (NSLS-II) [below], another DOE Office of Science User Facility. At the time, Yager was in the process of developing new equipment and techniques and looking for users for the Complex Materials Scattering (CMS) beamline, which the CFN and NSLS-II operate in partnership.

    “The group’s results were intriguing to me—both because they were able to create very small self-assembled structures, and because their results seemed to violate my expectations for the kinds of structures those materials should form,” said Yager.

    Sita and Nowak wrote and submitted a proposal for beam time at CMS. Their proposal was accepted, and the research Nowak conducted at the beamline ended up becoming a large part of her PhD thesis. In particular, she used a scattering technique called grazing-incidence small-angle x-ray scattering (GISAXS). In GISAXS, a high-energy x-ray beam reflects off of a thin film or substrate at a very shallow angle. The pattern of the scattered x-rays provides information about the size, structure, and orientation of any self-assembled structures within and on the surface.

    4
    Atomic force microscope images of a sugar-polyolefin conjugate ultrathin film (30 nanometers) at room temperature that the Sita Research Group heated to 140 degrees Fahrenheit for different lengths of time: (a) original ultrathin film, (b) after 14 hours, (c) a zoomed-in region corresponding to the white square in (b), (d) after 24 hours, (e) zoomed-in region corresponding to the white square in (d), and (f) after 48 hours. The images reveal how the morphology evolves in response to heating over time. Source: Journal of the American Chemical Society 2017, 139, 5281–5284.

    “The University of Maryland has a lab-scale x-ray source but we would have never discovered all that we did about the behavior of these materials without the in situ studies at NSLS-II,” said Nowak. “Scans that would have taken an hour in our lab only took 10 seconds at NSLS-II. We were able to visualize in real time how the materials responded to changes in temperature, film thickness, and polymer chain length.”

    The conjugate materials in this case were made out of cellobiose (a sugar derived from cellulose in plants) and polypropylene with a low molecular weight. From their studies, they learned that increasing the temperature caused several different well-ordered morphologies (structural arrangements) with very tiny feature sizes to emerge in both the bulk material and ultrathin films. By jumping to a specific temperature or slowly increasing the temperature, they could control which morphology they ended up with. And if the polymer chain was too long, the structures that formed were more limited in variety.

    “The results were beyond my expectations,” said Yager. “We were able to measure the ordering of Sam’s materials during annealing—that is, watch them during the process of self-organization. Surprisingly, these materials not only organized but also reorganized into a succession of different configurations as we raised the temperature. This behavior would have been hard to see by any other measurement technique.”

    “When the collaboration began, I was just beginning my research project,” said Nowak. “I didn’t know how useful the technique at NSLS-II would be to build upon the work the group had already done with these materials. But once I learned what GISAXS with a synchrotron source could do, it was perfect.”

    From user to postdoc

    During one of her visits to the NSLS-II for beam time, Yager mentioned to Nowak that he was looking for a postdoctoral researcher at the CFN.

    “I was so impressed by Sam’s diligence and scientific insight that I reached out to her when the CFN had the open postdoc position,” said Yager. “I knew she would continue to do great things if she joined our team.”

    Nowak had all intentions of working for industry immediately following graduation, but the combination of her experience as a user and conversation with Yager changed her mind.

    “Kevin explained the differences between the academic postdoc that I was picturing in my head and a postdoc at a place like the CFN,” said Nowak. “I knew that coming here would open a lot of doors for me.”

    Nowak received her PhD in August 2018 and joined the CFN in October.

    “I love it here,” said Nowak. “The research is interesting, and I’m learning so many new techniques and ideas that I would have not otherwise been exposed to. The environment at the CFN is very collaborative, and I get to meet lots of people who are pursuing very different research projects.”

    4
    Samantha Nowak (front row, left) recently joined the Center for Functional Nanomaterials as a postdoctoral researcher in the Electronic Nanomaterials Group, led by Kevin Yager (back row, second from right).

    The perfect blend

    Under the co-advisement of Yager and CFN Director Charles (Chuck) Black, Nowak is studying self-assembly using thin films of well-established polymers (polystyrene (PS) and poly(methyl methacrylate) (PMMA)) to create novel “non-native” morphologies (i.e., those that deviate from the bulk morphologies). Mainly, she is blending block copolymers with different intrinsic morphologies—the morphology they prefer to adopt based on the volume fraction, molecular weight, and surface energy of the respective blocks. For example, one block copolymer may form cylindrical nanostructures and the other lamellae. But when the block copolymers are blended, they adopt morphologies that are completely different than those of the individual components.

    After forming block copolymer thin films by spin casting them from solution onto a flat surface, Nowak heats them on a hot plate. Introducing heat provides energy for the block copolymer film to spontaneously order into patterns with nanoscale features. In order to more easily see the structure of the films, Nowak then converts the PMMA domains into an inorganic replica through sequential infiltration synthesis—a chemical method in which a polymer is infused with an inorganic material by exposure to gaseous metal precursors in multiple cycles—and etches away the polymer with oxygen plasma.

    “With this approach, I have better contrast when I look at the films in the scanning electron microscope,” said Nowak.

    Most recently, Nowak has been seeing what happens when she changes the composition of the block copolymer blend. One unexpected result so far was the formation of hexagonally perforated lamellae from cylinder and lamellae block copolymers.

    “This morphology is not very common and is difficult to obtain,” explained Nowak. “There’s a very narrow region of the phase diagram where it is stable, so the fact that we expanded accessibility to this phase is very exciting.”

    In another experiment, Nowak used the same exact blend of block copolymers but changed the surface energy. The result was either a single nanostructure or a combination of line and dot patterns, hexagonally perforated lamellae, and horizontal lamellae. Nowak is also exploring how to chemically pattern substrates as a way to “program” which morphologies appear in particular regions of the substrate. She is in the process of getting training in the cleanroom of the CFN Nanofabrication Facility to perform this patterning.

    “We’re creating new nanostructures from already existing materials,” explained Nowak. “We don’t have to synthesize new types of block copolymers; we can use two easily obtainable ones and broaden what we can do with them.”

    The combination of different nanostructures within a single substrate in a predetermined fashion could expand the range of applications—something that Nowak had not previously thought much about.

    5
    Conventionally, block copolymers self-assemble into a limited range of morphologies, such as spheres and lamellae. But by using appropriate block copolymer blends and a chemically patterned substrate that contains the “instructions” for which morphologies appear where, scientists can significantly expand this range. Nowak, Yager, and other CFN scientists recently obtained four different nanostructures—dots, lines, horizontal lamellae, and hexagonally perforated lamellae—in predetermined regions of a single substrate.

    “As a chemist, I tend to focus on the very specific details of the research,” said Nowak. “That is where my brain is trained to stop. But, Chuck—who I meet with every other week to discuss my research and goals—has helped me broaden my viewpoint. He has me consider how we could use these nanostructures in different ways, how we can benefit society with them. I’ve always been interested in the fundamental science part, but now I’m retraining my mind to see the bigger picture. I’ll need to be able to look beyond my individual research projects for a career in industry.”

    After her postdoc, Nowak plans to enter industry as a polymer chemist. She has not yet decided which industry, but she is currently considering cosmetics or consumer goods.

    “One of my grandfather’s inventions was a way to stabilize color in paints and coatings,” said Nowak. “Before his invention, paint darkened or discolored exponentially faster than paints today. Now almost all paints today have this stabilizer in it. It would be great to follow in my grandfather’s footsteps.”

    See the full article here .


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

    Please help promote STEM in your local schools.

    Stem Education Coalition

    BNL Campus


    BNL Center for Functional Nanomaterials

    BNL NSLS-II


    BNL NSLS II

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    BNL RHIC PHENIX

    One of ten national laboratories overseen and primarily funded by the Office of Science of the U.S. Department of Energy (DOE), Brookhaven National Laboratory conducts research in the physical, biomedical, and environmental sciences, as well as in energy technologies and national security. Brookhaven Lab also builds and operates major scientific facilities available to university, industry and government researchers. The Laboratory’s almost 3,000 scientists, engineers, and support staff are joined each year by more than 5,000 visiting researchers from around the world. Brookhaven is operated and managed for DOE’s Office of Science by Brookhaven Science Associates, a limited-liability company founded by Stony Brook University, the largest academic user of Laboratory facilities, and Battelle, a nonprofit, applied science and technology organization.
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  • richardmitnick 12:50 pm on April 5, 2019 Permalink | Reply
    Tags: "Putting a New Spin on Majorana Fermions", , BNL, , Majorana fermions are particle-like excitations called quasiparticles that emerge as a result of the fractionalization (splitting) of individual electrons into two halves., , , , , Spin ladders- crystals formed of atoms with a three-dimensional (3-D) structure subdivided into pairs of chains that look like ladders.   

    From Brookhaven National Lab: “Putting a New Spin on Majorana Fermions” 

    From Brookhaven National Lab

    April 1, 2019
    Ariana Tantillo
    atantillo@bnl.gov
    (631) 344-2347

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

    Split electrons that emerge at the boundaries between different magnetic states in materials known as spin ladders could act as stable bits of information in next-generation quantum computers.

    2
    Theoretical calculations performed by (left to right) Neil Robinson, Robert Konik, Alexei Tsvelik, and Andreas Weichselbaum of Brookhaven Lab’s Condensed Matter Physics and Materials Science Department suggest that Majorana fermions exist in the boundaries of magnetic materials with different magnetic phases. Majorana fermions are particle-like excitations that emerge when single electrons fractionalize into two halves, and their unique properties are of interest for quantum applications.

    The combination of different phases of water—solid ice, liquid water, and water vapor—would require some effort to achieve experimentally. For instance, if you wanted to place ice next to vapor, you would have to continuously chill the water to maintain the solid phase while heating it to maintain the gas phase.

    For condensed matter physicists, this ability to create different conditions in the same system is desirable because interesting phenomena and properties often emerge at the interfaces between two phases. Of current interest is the conditions under which Majorana fermions might appear near these boundaries.

    Majorana fermions are particle-like excitations called quasiparticles that emerge as a result of the fractionalization (splitting) of individual electrons into two halves. In other words, an electron becomes an entangled (linked) pair of two Majorana quasiparticles, with the link persisting regardless of the distance between them. Scientists hope to use Majorana fermions that are physically separated in a material to reliably store information in the form of qubits, the building blocks of quantum computers. The exotic properties of Majoranas—including their high insensitivity to electromagnetic fields and other environmental “noise”—make them ideal candidates for carrying information over long distances without loss.

    However, to date, Majorana fermions have only been realized in materials at extreme conditions, including at frigid temperatures close to absolute zero (−459 degrees Fahrenheit) and under high magnetic fields. And though they are “topologically” protected from local atomic impurities, disorder, and defects that are present in all materials (i.e., their spatial properties remain the same even if the material is bent, twisted, stretched, or otherwise distorted), they do not survive under strong perturbations. In addition, the range of temperatures over which they can operate is very narrow. For these reasons, Majorana fermions are not yet ready for practical technological application.

    Now, a team of physicists led by the U.S. Department of Energy’s (DOE) Brookhaven National Laboratory and including collaborators from China, Germany, and the Netherlands has proposed a novel theoretical method for producing more robust Majorana fermions. According to their calculations, as described in a paper published on Jan. 15 in Physical Review Letters, these Majoranas emerge at higher temperatures (by many orders of magnitude) and are largely unaffected by disorder and noise. Even though they are not topologically protected, they can persist if the perturbations change slowly from one point to another in space.

    “Our numerical and analytical calculations provide evidence that Majorana fermions exist in the boundaries of magnetic materials with different magnetic phases, or directions of electron spins, positioned next to one other,” said co-author Alexei Tsvelik, senior scientist and leader of the Condensed Matter Theory Group in Brookhaven Lab’s Condensed Matter Physics and Materials Science (CMPMS) Department. “We also determined the number of Majorana fermions you should expect to get if you combine certain magnetic phases.”

    For their theoretical study, the scientists focused on magnetic materials called spin ladders, which are crystals formed of atoms with a three-dimensional (3-D) structure subdivided into pairs of chains that look like ladders. Though the scientists have been studying the properties of spin ladder systems for many years and expected that they would produce Majorana fermions, they did not know how many. To perform their calculations, they applied the mathematical framework of quantum field theory for describing the fundamental physics of elementary particles, and a numerical method (density-matrix renormalization group) for simulating quantum systems whose electrons behave in a strongly correlated way.

    “We were surprised to learn that for certain configurations of magnetic phases we can generate more than one Majorana fermion at each boundary,” said co-author and CMPMS Department Chair Robert Konik.

    For Majorana fermions to be practically useful in quantum computing, they need to be generated in large numbers. Computing experts believe that the minimum threshold at which quantum computers will be able to solve problems that classical computers cannot is 100 qubits. The Majorana fermions also have to be moveable in such a way that they can become entangled.

    The team plans to follow up their theoretical study with experiments using engineered systems such as quantum dots (nanosized semiconducting particles) or trapped (confined) ions. Compared to the properties of real materials, those of engineered ones can be more easily tuned and manipulated to introduce the different phase boundaries where Majorana fermions may emerge.

    “What the next generation of quantum computers will be made of is unclear right now,” said Konik. “We’re trying to find better alternatives to the low-temperature superconductors of the current generation, similar to how silicon replaced germanium in transistors. We’re in such early stages that we need to explore every possibility available.”

    See the full article here .


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

    Please help promote STEM in your local schools.

    Stem Education Coalition

    BNL Campus

    BNL NSLS-II


    BNL NSLS II

    BNL RHIC Campus

    BNL/RHIC Star Detector

    BNL RHIC PHENIX

    One of ten national laboratories overseen and primarily funded by the Office of Science of the U.S. Department of Energy (DOE), Brookhaven National Laboratory conducts research in the physical, biomedical, and environmental sciences, as well as in energy technologies and national security. Brookhaven Lab also builds and operates major scientific facilities available to university, industry and government researchers. The Laboratory’s almost 3,000 scientists, engineers, and support staff are joined each year by more than 5,000 visiting researchers from around the world. Brookhaven is operated and managed for DOE’s Office of Science by Brookhaven Science Associates, a limited-liability company founded by Stony Brook University, the largest academic user of Laboratory facilities, and Battelle, a nonprofit, applied science and technology organization.
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  • richardmitnick 6:03 pm on March 8, 2019 Permalink | Reply
    Tags: , , BNL,   

    From Brookhaven National Lab: “NETL Develops an Improved Process for Creating Building Blocks for $200 Billion Per Year Chemical Industry Market” 

    From Brookhaven National Lab

    March 6, 2019
    Stephanie Kossman
    skossman@bnl.gov

    1

    National Energy Technology Laboratory (NETL) researchers developed a new catalyst that can selectively convert syngas into light hydrocarbon compounds called olefins for application in a $200 billion per year chemical industry market. The work has been detailed in ChemCatChem, a premier catalysis journal.

    The catalyst was characterized using a variety of techniques from U.S. Department of Energy user facilities at Brookhaven National Laboratory including advanced electron microscopy at the Center for Functional Nanomaterials and synchrotron-based X-ray spectroscopy conducted at the National Synchrotron Light Source II.

    An olefin is a compound made up of hydrogen and carbon that contains one or more pairs of carbon atoms linked by a double bond. Because of their high reactivity and low cost, olefins are widely used as building blocks in the manufacture of plastics and the preparation of certain types of synthetic rubber, chemical fibers, and other commercially valuable products.

    The NETL research is significant because light olefins are currently produced using steam cracking of ethane or petroleum derived precursors. Steam cracking is a petrochemical process in which saturated hydrocarbons are broken down into smaller, often unsaturated hydrocarbons. It is one of the most energy intensive processes in the chemical industry. Research has been underway to develop alternative approaches to producing olefins that are less energy intensive, more sustainable and can use different feedstocks. The NETL research has shown promising results toward those goals.

    According to NETL researchers Congjun Wang and Christopher Matranga, the research led to development of a carbon nanosheet-supported iron oxide catalyst that has proven effective in converting syngas into light olefins. A catalyst is a substance that increases the rate of a chemical reaction without itself undergoing any permanent chemical change. A nanosheet is a two-dimensional nanostructure with thickness ranging from 1 to 100 nanometers.

    The carbon nanosheet-supported iron oxide catalyst was put to the test in the Fischer-Tropsch to Olefins synthesis process —a set of chemical reactions that changes a mixture of carbon monoxide gas and hydrogen gas into hydrocarbons that is showing promise as a method for creating olefins at lower cost.

    “The NETL-developed carbon nanosheets-supported iron oxide catalysts demonstrated extremely high activity that was 40 to 1,000 time higher than other catalysts used in the Fischer-Tropsch to Olefins process,” Wang said. “In addition, it was extraordinarily robust with no degradation observed after up to 500 hours of repeated catalytic reactions.”

    Matranga added that the carbon nanosheets promoted the effective transformation of iron oxide in the fresh catalysts to active iron carbide under reaction conditions.

    “This effect was not seen in other carbon-based catalyst support materials such as carbon nanotubes,” he said. “It is a result of the potassium citrate we use to make the carbon support. The potassium has a promotion effect on the catalyst in a manner that cannot be achieved by just adding potassium to the carbon support.”

    Eli Stavitski, a physicist at Brookhaven’s NSLS-II’s Inner Shell Spectroscopy (ISS) beamline, said the new catalyst performed well in his tests. ISS was one of the two beamlines at NSLS-II where the work was conducted.

    “Using the exceptionally bright X-ray beams available at NSLS-II, we were able to confirm that the new catalyst developed by the NETL team transforms into an active, iron carbide phase faster, and more completely, than the materials proposed for the Fischer Tropsch synthesis before,” he said.

    See the full article here .


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

    Please help promote STEM in your local schools.

    Stem Education Coalition

    BNL Campus

    BNL 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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