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  • richardmitnick 10:21 am on June 26, 2020 Permalink | Reply
    Tags: "Dance Electron Dance: Scientists Use Light to Choreograph Electronic Motion in 2D Materials", , , How electrons move and interact within materials, LBNL Lawrence Berkeley National Lab, , Moiré superlattices provide a unique method for introducing exotic electronic behavior in materials where they don’t typically exist., , , Using light to choreograph electron spin.   

    From Lawrence Berkeley National Lab: “Dance, Electron, Dance: Scientists Use Light to Choreograph Electronic Motion in 2D Materials” 


    From Lawrence Berkeley National Lab

    June 26, 2020
    Theresa Duque
    tnduque@lbl.gov
    (510) 424-2866

    Study led by Berkeley Lab, UC Berkeley could advance understanding of electron interactions for quantum devices.

    1
    Microscope image of the TMD moiré superlattice device. (Credit: Emma Regan/Berkeley Lab)

    A team of scientists led by the Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab) and UC Berkeley has demonstrated a powerful new technique that uses light to measure how electrons move and interact within materials. With this technique, the researchers observed exotic states of matter in stacks of atomically thin semiconductors called transition metal dichalcogenide (TMD) moiré superlattices.

    Their study, which was published in the journal Nature, is the first to prove that interactions between electrons play a significant role in how charge flows in TMD moiré superlattices.

    “Moiré superlattices provide a unique method for introducing exotic electronic behavior in materials where they don’t typically exist,” said lead author Emma Regan, a doctoral researcher in Berkeley Lab’s Materials Sciences Division and the UC Berkeley physics department. “Understanding and engineering electronic behavior in quantum materials may provide new approaches for electronic devices in the future.”

    In most materials, electrons move fast and rarely interact. But in previous studies, other researchers have shown that a moiré superlattice – which creates an energy landscape for electrons – can slow the electrons down enough that they feel interactions between each other.

    “We suspected that these electron-electron interactions in TMD moiré superlattices are very strong – even stronger than what you would find in stacks of graphene,” said Regan.

    Typically, physicists investigate electron-electron interactions by attaching wires to a material and measuring how easily electrical current flows. But in stacks of TMDs, electrons don’t flow easily between the wires and the material, which makes it difficult to understand how the electrons interact.

    So the researchers turned to light instead.

    The research team, led by senior author Feng Wang, fabricated the TMD moiré superlattice from atomically thin layers of tungsten diselenide and tungsten disulfide – two common semiconductors known for their ability to efficiently absorb and emit light. They then formed a device just 25 nanometers (25 billionths of a meter) thick by sandwiching the tungsten diselenide/tungsten disulfide moiré superlattice between boron nitride and graphene.

    In Wang’s ultrafast nano-optics lab, the researchers shone lasers on the TMD device to observe how electrons flowed in the superlattice as they varied the number of electrons injected into the material. Wang is a faculty scientist in Berkeley Lab’s Materials Sciences Division and professor of physics at UC Berkeley.

    Using light to choreograph electron spin

    3
    Electrons resting in the moire superlattice at different electron densities. Wigner crystal states are shown left and center. Typical insulating state is shown right. (Credit: Emma Regan/Berkeley Lab)

    As expected, the researchers uncovered evidence of very strong electron-electron interactions in the TMD moiré superlattice device.

    In one experiment, for example, the device suddenly became electrically insulating – the electrons stopped moving – when they added enough electrons to fill each unit cell in the moiré superlattice.

    This behavior is common in a material with strong electron-electron interactions, Regan said. “Since the electrons interact strongly, they prefer not to sit at the same position because this will increase their energy. If all of the unit cells are already occupied, then the electrons stop moving around,” she explained.

    So Regan and co-authors were surprised to see similar insulating behavior in the TMD moiré superlattice device when there were fewer electrons in the material, and not all the superlattice unit cells were occupied.

    “Electron interactions were so strong in the TMD moiré superlattice that electrons also avoided sitting on neighboring sites,” she said. “These states are called generalized Wigner crystal states and haven’t been seen in any other moiré superlattice system.”

    TMDs have a unique property where different polarizations of light can excite electrons to spin up or spin down, so the researchers used a laser to inject electrons with “spin up” or “spin down” into the material, probing their behavior with a second laser. “Direct optical access to the electron spin is special because it helps us understand the details of these exotic states,” Regan said.

    “This study is very exciting because we were able to demonstrate strong electron-electron interactions in TMD moiré superlattices, which also have fascinating and useful optical properties,” she added. “This work weds traditional correlated electron physics with 2D TMD materials – two communities that usually don’t overlap.”

    The researchers hope to further develop their technique to take optical measurements of electron spin at tiny scales of distance and timing.

    Researchers from the Kavli Institute at Cornell for Nanoscale Science; Huazhong University of Science and Technology, and the University of the Chinese Academy of Sciences, China; Arizona State University; Lund University, Sweden; and the National Institute for Materials Science, Japan, also contributed to the study.

    The work was supported by the DOE Office of Science. Additional funding was provided by the U.S. Army Research Office.

    See the full article here .

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

    Please help promote STEM in your local schools.

    Stem Education Coalition

    LBNL campus

    LBNL Molecular Foundry

    Bringing Science Solutions to the World
    In the world of science, Lawrence Berkeley National Laboratory (Berkeley Lab) is synonymous with “excellence.” Thirteen Nobel prizes are associated with Berkeley Lab. Seventy Lab scientists are members of the National Academy of Sciences (NAS), one of the highest honors for a scientist in the United States. Thirteen of our scientists have won the National Medal of Science, our nation’s highest award for lifetime achievement in fields of scientific research. Eighteen of our engineers have been elected to the National Academy of Engineering, and three of our scientists have been elected into the Institute of Medicine. In addition, Berkeley Lab has trained thousands of university science and engineering students who are advancing technological innovations across the nation and around the world.

    Berkeley Lab is a member of the national laboratory system supported by the U.S. Department of Energy through its Office of Science. It is managed by the University of California (UC) and is charged with conducting unclassified research across a wide range of scientific disciplines. Located on a 202-acre site in the hills above the UC Berkeley campus that offers spectacular views of the San Francisco Bay, Berkeley Lab employs approximately 3,232 scientists, engineers and support staff. The Lab’s total costs for FY 2014 were $785 million. A recent study estimates the Laboratory’s overall economic impact through direct, indirect and induced spending on the nine counties that make up the San Francisco Bay Area to be nearly $700 million annually. The Lab was also responsible for creating 5,600 jobs locally and 12,000 nationally. The overall economic impact on the national economy is estimated at $1.6 billion a year. Technologies developed at Berkeley Lab have generated billions of dollars in revenues, and thousands of jobs. Savings as a result of Berkeley Lab developments in lighting and windows, and other energy-efficient technologies, have also been in the billions of dollars.

    Berkeley Lab was founded in 1931 by Ernest Orlando Lawrence, a UC Berkeley physicist who won the 1939 Nobel Prize in physics for his invention of the cyclotron, a circular particle accelerator that opened the door to high-energy physics. It was Lawrence’s belief that scientific research is best done through teams of individuals with different fields of expertise, working together. His teamwork concept is a Berkeley Lab legacy that continues today.

    A U.S. Department of Energy National Laboratory Operated by the University of California.

    University of California Seal

     
  • richardmitnick 9:43 am on June 24, 2020 Permalink | Reply
    Tags: "Introducing a New Isotope: Mendelevium-244", , , In the latest discovery the team used Berkeley Lab’s 88-Inch Cyclotron., LBNL Lawrence Berkeley National Lab, The FIONA instrument at Berkeley Lab’s 88-Inch Cyclotron was key in confirming the discovery of mendelevium-244.   

    From Lawrence Berkeley National Lab: “Introducing a New Isotope: Mendelevium-244” 


    From Lawrence Berkeley National Lab

    Berkeley Lab-led team creates a new, lighter form of the element mendelevium in experiments at the 88-Inch Cyclotron.

    LBNL 88 inch cyclotron

    The making of mendelevium-244: In this video, Berkeley Lab project scientist Jennifer Pore describes how scientists working at Berkeley Lab’s 88-Inch Cyclotron created and confirmed the discovery of a new isotope, mendelevium-244. Mendelevium, an artificial element, was first discovered by a Berkeley Lab team in 1955, and since then more than a dozen variations of this element, known as isotopes, have been discovered. (Credit: Marilyn Sargent/Berkeley Lab)

    A team of scientists working at Lawrence Berkeley National Laboratory (Berkeley Lab) has discovered a new form of the human-made element mendelevium. The newly created isotope, mendelevium-244, is the 17th and lightest form of mendelevium, which is element 101 on the periodic table.

    Mendelevium was first created by Berkeley Lab scientists in 1955 (see a related video), and is among a list of 16 elements that Berkeley Lab scientists discovered or helped to discover. An isotope is a form of an element with more or fewer neutrons (uncharged particles) in its atomic nucleus than other forms of an element.

    In the latest discovery, the team used Berkeley Lab’s 88-Inch Cyclotron, which accelerates powerful beams of charged particles at targets to create atoms of heavier elements, to make mendelevium-244. A cyclotron is a type of particle accelerator that was invented by the Lab’s namesake, Ernest O. Lawrence, in 1930.

    Berkeley Lab-led teams have now discovered 12 of the 17 mendelevium isotopes, and have discovered a total of 640 isotopes – about one-fifth of all known isotopes and by far the highest count for a single institution. At the close of 2019 there were 3,308 known isotopes. The new isotope discovery is the first by a Berkeley Lab-led team since 2010.

    “It was challenging to discover this new isotope of mendelevium because all of the neighboring mendelevium isotopes have very similar decay properties,” said Jennifer Pore, a Berkeley Lab project scientist who led the study detailing the isotope’s discovery. Alpha decay describes the process by which a radioactive element like mendelevium breaks down into lighter elements over time.

    2
    A model showing the 101 electrons orbiting the element mendelevium. (Credit: Pumbaa, Greg Robson/Wikimedia Commons)

    In total, the team measured the properties of 10 atoms of mendelevium-244 for the study, which appeared today in the journal Physical Review Letters.

    “Each isotope represents a unique combination of protons and neutrons,” Pore said. “When a new isotope is discovered, that particular combination of protons (positively charged particles) and neutrons has never been observed. Studies of these extreme combinations are critical toward our understanding of all nuclear matter.”

    In addition to discovering the new isotope, the research team’s work also provided the first direct evidence for a decay process involving an isotope of the element berkelium. The team included scientists from UC Berkeley, Lawrence Livermore National Laboratory, San Jose State University, and Sweden’s Lund University.

    Researchers found evidence that mendelevium-244 has two separate chains of decay, each leading to a different half-life: 0.4 second and 6 seconds, based on different energy configurations of particles in its nucleus. A half-life is the time it takes for a radioactive element’s number of atoms to be reduced by half as their nuclei decay into other, lighter nuclei.

    In a separate measurement stemming from the same study, the researchers found the first evidence for the alpha decay process of berkelium-236, an isotope of the element berkelium, as it transforms into americium-232, a slightly lighter isotope. Berkelium was discovered in 1949 by a Berkeley Lab-led team.

    Central to the isotope’s discovery was an instrument at the 88-Inch Cyclotron called FIONA, or For the Identification Of Nuclide A. The “A” in FIONA represents an element’s mass number, which is the total number of protons (positively charged particles) and neutrons (uncharged particles) in an atom’s nucleus. The new isotope’s mass number is 244.

    “The most important tool that we had in this discovery was FIONA,” said Pore, who was also part of the team that assisted in FIONA’s testing and startup. FIONA precisely measured the mass number of the new isotope.

    Barbara Jacak, Nuclear Science Division director at Berkeley Lab, said, “We built FIONA to enable discoveries like this one, and it is exciting to see this instrument hitting its stride.”

    3
    The FIONA instrument at Berkeley Lab’s 88-Inch Cyclotron was key in confirming the discovery of mendelevium-244. (Credit: Marilyn Sargent/Berkeley Lab)

    Michael Thoennessen, a University Distinguished Professor at Michigan State University who is on leave to serve as editor in chief of the American Physical Society, maintains a list of isotope discoveries and notes that the list of new isotopes has been thinner than usual over the past several years.

    “Isotope discoveries are cyclical and depend on new accelerators and major advances in experimental equipment development,” he said. Berkeley Lab’s FIONA and the Facility for Rare Isotope Beams (FRIB), a U.S. Department of Energy user facility in development at Michigan State University, are unique capabilities “with large discovery potential” for different types of new isotopes in the U.S., he noted.

    To ensure that FIONA’s measurements were accurate, the research team first measured the decay properties and mass numbers of known mendelevium isotopes, including mendelevium-247, mendelevium-246, and mendelevium-245.

    “Once we were confident that we were well-versed in the properties of these light mendelevium isotopes, we attempted the experiment to discover the previously unobserved isotope mendelevium-244,” Pore said. “Without the direct confirmation that we had produced an isotope with a mass number of 244, it would have been very difficult to disentangle the results and prove the discovery.”

    To create such exotic isotopes – even the lightest known form of mendelevium is still heavier than naturally occurring uranium – scientists produced a particle beam at the 88-Inch Cyclotron containing charged particles of argon-40, an isotope of argon, and directed the beam at a thin foil target composed of bismuth-209, an isotope of bismuth.

    Occasionally in these experiments, a nucleus in the high-energy particle beam directly strikes and fuses with a nucleus in the target foil, producing a single atom of a heavier element. And for an isotope with a very short half-life, it’s a race to take measurements of an atom before it decays away into something else.

    Berkeley’s 88-Inch Cyclotron has another tool upstream of FIONA that is called the Berkeley Gas-Filled Separator. The separator helps pull out the relevant atoms that can be quickly and individually measured in detail with FIONA.

    Researchers may pursue other studies of mendelevium-244 with other instrumentation to try to learn more about its structure, Pore said.

    And now that FIONA has demonstrated its value in isotope discovery, Berkeley Lab researchers are setting their sights on other new isotopes. “We are already planning similar studies along other isotopic chains to discover new isotopes,” Pore 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

    LBNL campus

    LBNL Molecular Foundry

    Bringing Science Solutions to the World
    In the world of science, Lawrence Berkeley National Laboratory (Berkeley Lab) is synonymous with “excellence.” Thirteen Nobel prizes are associated with Berkeley Lab. Seventy Lab scientists are members of the National Academy of Sciences (NAS), one of the highest honors for a scientist in the United States. Thirteen of our scientists have won the National Medal of Science, our nation’s highest award for lifetime achievement in fields of scientific research. Eighteen of our engineers have been elected to the National Academy of Engineering, and three of our scientists have been elected into the Institute of Medicine. In addition, Berkeley Lab has trained thousands of university science and engineering students who are advancing technological innovations across the nation and around the world.

    Berkeley Lab is a member of the national laboratory system supported by the U.S. Department of Energy through its Office of Science. It is managed by the University of California (UC) and is charged with conducting unclassified research across a wide range of scientific disciplines. Located on a 202-acre site in the hills above the UC Berkeley campus that offers spectacular views of the San Francisco Bay, Berkeley Lab employs approximately 3,232 scientists, engineers and support staff. The Lab’s total costs for FY 2014 were $785 million. A recent study estimates the Laboratory’s overall economic impact through direct, indirect and induced spending on the nine counties that make up the San Francisco Bay Area to be nearly $700 million annually. The Lab was also responsible for creating 5,600 jobs locally and 12,000 nationally. The overall economic impact on the national economy is estimated at $1.6 billion a year. Technologies developed at Berkeley Lab have generated billions of dollars in revenues, and thousands of jobs. Savings as a result of Berkeley Lab developments in lighting and windows, and other energy-efficient technologies, have also been in the billions of dollars.

    Berkeley Lab was founded in 1931 by Ernest Orlando Lawrence, a UC Berkeley physicist who won the 1939 Nobel Prize in physics for his invention of the cyclotron, a circular particle accelerator that opened the door to high-energy physics. It was Lawrence’s belief that scientific research is best done through teams of individuals with different fields of expertise, working together. His teamwork concept is a Berkeley Lab legacy that continues today.

    A U.S. Department of Energy National Laboratory Operated by the University of California.

    University of California Seal

     
  • richardmitnick 11:57 am on June 18, 2020 Permalink | Reply
    Tags: "Off the Scales: Fish Armor Both Tough and Flexible", , High-tech imaging of carp scales by Berkeley Lab scientists reveals remarkable properties that could lead to advanced synthetic materials., LBNL Lawrence Berkeley National Lab,   

    From Lawrence Berkeley National Lab: “Off the Scales: Fish Armor Both Tough and Flexible” 


    From Lawrence Berkeley National Lab

    June 18, 2020
    Julie Chao
    JHChao@lbl.gov
    (510) 486-6491

    High-tech imaging of carp scales by Berkeley Lab scientists reveals remarkable properties that could lead to advanced synthetic materials.

    1
    Carp scales are highly resistant to penetration. Advanced X-ray imaging techniques have revealed why. (Credit: Vladimir Wrangel/ Shutterstock)

    Humans have drawn technological inspiration from fish scales going back to ancient times: Romans, Egyptians, and other civilizations would dress their warriors in scale armor, providing both protection and mobility. Now, using advanced X-ray imaging techniques, Lawrence Berkeley National Laboratory (Berkeley Lab) scientists have characterized carp scales down to the nanoscale, enabling them to understand how the material is resistant to penetration while retaining flexibility.

    The researchers used powerful X-ray beams at Berkeley Lab’s Advanced Light Source (ALS) to watch how the fibers in carp scales react as stress is applied.

    LBNL ALS

    As they wrote in their paper, published recently in the journal Matter, what they found “may well provide further inspiration for the design of advanced synthetic structural materials with unprecedented toughness and penetration resistance.”

    “The structure of biological materials is absolutely fascinating,” said lead author Robert Ritchie, of Berkeley Lab’s Materials Sciences Division, who headed this work with Marc Meyers, a professor of nanoengineering and mechanical engineering at UC San Diego. “We like to mimic these properties in engineering materials, but the first step is to see how nature does it.”

    Fish scales have a hard outer shell with a softer inner layer that is tough and ductile. When something like a predator’s teeth try to sink into the scales, the outer shell resists the penetration but the inner has to absorb all the excess load to keep the scale in one piece. How does it do this? It turns out that the fibers in the scale, which is made up of collagen plus minerals, are in a twisted orientation, called a Bouligand structure. When stress is applied to the material, the fibers rotate in sequence in order to absorb the excess load.

    “It’s called adaptive reorientation. It’s like a smart material,” said Ritchie, who is also a professor of materials science and engineering at UC Berkeley. “Using a technique called small angle X-ray scattering, we can follow that in real time using the synchrotron. We irradiate it with X-rays, and we can actually see the fibers rotating and moving.”

    The collagen that makes up human skin, on the other hand, is “all messed up like a bowl of spaghetti, but it can unravel and align to absorb energy, which makes skin incredibly resistant to tearing,” Ritchie said. The Bouligand structure in the carp scale is much more organized but still makes for a very effective toughening mechanism.

    2
    Optical microscopy image of the cross-section of a carp scale showing a multilayered structure. (Credit: Quan et al., Structure and Mechanical Adaptability of a Modern Elasmoid Fish Scale from the Common Carp, Matter [above])

    The other noteworthy characteristic of a carp scale is the gradient between the hard and soft layers. “If we were making that as armor, we would have an interface between the hard and soft material. The interface is invariably a location where cracks and failures start,” said Ritchie, an expert in how materials fail. “The way nature does it: Instead of having these interfaces where there’s discontinuity between one material and another, nature makes a perfect gradient from the hard to the soft (tougher) material.”

    Working in collaboration with the researchers at UC San Diego, the team has previously studied the arapaima, an Amazonian freshwater fish whose scales are so tough they are impenetrable to piranha, as well as other species. For this study they chose the carp, a modern version of the ancient coelacanth fish, also known for having scales that act as armor.

    Now that the deformation and failure mechanisms of carp scales have been characterized, trying to reproduce these properties in an engineering material is the next challenge. Ritchie noted that advances in 3D printing could provide a way to produce gradients the way nature does, and thus make a material that is both hard and ductile.

    “Once we get a better handle on how to manipulate 3D printing, we can start to make more materials in the image of nature,” he said.

    The ALS is a Department of Energy Office of Science user facility. The study was supported by a grant from the Air Force Office of Scientific Research.

    See the full article here .

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

    Please help promote STEM in your local schools.

    Stem Education Coalition

    LBNL campus

    LBNL Molecular Foundry

    Bringing Science Solutions to the World
    In the world of science, Lawrence Berkeley National Laboratory (Berkeley Lab) is synonymous with “excellence.” Thirteen Nobel prizes are associated with Berkeley Lab. Seventy Lab scientists are members of the National Academy of Sciences (NAS), one of the highest honors for a scientist in the United States. Thirteen of our scientists have won the National Medal of Science, our nation’s highest award for lifetime achievement in fields of scientific research. Eighteen of our engineers have been elected to the National Academy of Engineering, and three of our scientists have been elected into the Institute of Medicine. In addition, Berkeley Lab has trained thousands of university science and engineering students who are advancing technological innovations across the nation and around the world.

    Berkeley Lab is a member of the national laboratory system supported by the U.S. Department of Energy through its Office of Science. It is managed by the University of California (UC) and is charged with conducting unclassified research across a wide range of scientific disciplines. Located on a 202-acre site in the hills above the UC Berkeley campus that offers spectacular views of the San Francisco Bay, Berkeley Lab employs approximately 3,232 scientists, engineers and support staff. The Lab’s total costs for FY 2014 were $785 million. A recent study estimates the Laboratory’s overall economic impact through direct, indirect and induced spending on the nine counties that make up the San Francisco Bay Area to be nearly $700 million annually. The Lab was also responsible for creating 5,600 jobs locally and 12,000 nationally. The overall economic impact on the national economy is estimated at $1.6 billion a year. Technologies developed at Berkeley Lab have generated billions of dollars in revenues, and thousands of jobs. Savings as a result of Berkeley Lab developments in lighting and windows, and other energy-efficient technologies, have also been in the billions of dollars.

    Berkeley Lab was founded in 1931 by Ernest Orlando Lawrence, a UC Berkeley physicist who won the 1939 Nobel Prize in physics for his invention of the cyclotron, a circular particle accelerator that opened the door to high-energy physics. It was Lawrence’s belief that scientific research is best done through teams of individuals with different fields of expertise, working together. His teamwork concept is a Berkeley Lab legacy that continues today.

    A U.S. Department of Energy National Laboratory Operated by the University of California.

    University of California Seal

     
  • richardmitnick 10:15 am on June 17, 2020 Permalink | Reply
    Tags: , , , LBNL Lawrence Berkeley National Lab, , , , Some Lab Magnet Work Proceeds on Particle Accelerator Upgrade"   

    From Lawrence Berkeley National Lab: “Some Lab Magnet Work Proceeds on Particle Accelerator Upgrade” 


    From Lawrence Berkeley National Lab

    June 17, 2020
    Glenn Roberts Jr.
    geroberts@lbl.gov
    (510) 520-0843

    Berkeley Lab team prepares for a resumption in assembly work after pause due to pandemic.

    1
    Andy Lin, left, lead cabling technician, and Elizabeth Lee, a quality assurance engineer, install diagnostics on the Rutherford Cabling machine at Berkeley Lab while complying with social-distancing and safety rules. The machine, equipped with dozens of spools of wire, produces high-current superconducting cables for the High-Luminosity LHC Accelerator Upgrade Project. (Credit: Elizabeth Lee/Berkeley Lab)

    While COVID-19 risks had led to a temporary halt in fabrication work on high-power superconducting magnets built by a collaboration of three U.S. Department of Energy (DOE) national labs for an upgrade of the world’s largest particle collider at CERN in Europe, researchers at Lawrence Berkeley National Laboratory (Berkeley Lab) are still carrying out some project tasks.

    “Scientific and engineering staff continue to work on project documentation, procurements, and planning,” said Dan Cheng, a Berkeley Lab engineer who oversees magnet assembly activities at Berkeley Lab for the three-lab U.S. Large Hadron Collider (LHC) Accelerator Upgrade Project.

    Ian Pong, a scientist in charge of cable fabrication – the other task that is managed by Berkeley Lab – added, “We actually just had a couple of new staff join the team, and we took the opportunity to provide training also.”

    The project is part of an international effort to upgrade CERN’s LHC to provide for a larger number of particle collisions – the High-Luminosity LHC (HL-LHC) (see a related video).

    2
    Ian Pong, materials project scientist and lab cable task leader, inspects a cable in this 2016 photo. (Credit: Marilyn Sargent/Berkeley Lab.)

    Soren Prestemon, director of the DOE’s U.S. Magnet Development Program and the Berkeley Center for Magnet Technology, said, “We are developing administrative and engineering controls to allow us to resume our assembly and cabling tasks while still following safe social distancing guidelines. We follow Berkeley Lab guidance on work planning and on-site staff presence.”

    Prestemon is deputy division director of technology for the Accelerator Technology and Applied Physics (ATAP) Division at Berkeley Lab. Pong is a staff scientist in ATAP, and Cheng is a member of the Engineering Division.

    Cheng noted that the pause in assembly work will inevitably impact the project’s schedule, and social distancing requirements and reduced on-site staffing as Berkeley Lab moves to reopen some activities in a safe and limited way will likely affect efficiency and productivity for a time.

    “We expect our operations will take some time ramping up back to full speed,” he said.

    Pong agreed, “Although the Lab reopened on June 1, the restart is not a sprint but just the beginning of a marathon.”

    3
    Berkeley Lab technicians Ahmet Pekedis, left, and Joshua Herrera assemble the third pre-production magnet for the HL-LHC AUP project. The magnet is expected to ship to Brookhaven National Laboratory for testing in September. (Credit: Dan Cheng/Berkeley Lab)

    Some vendors to the U.S. magnet development effort have suffered delays during the pandemic, Cheng noted, though most of the major vendors have been able to continue their work in manufacturing magnet components for the effort.

    In all, Berkeley Lab, Fermi National Accelerator Laboratory (Fermilab), and Brookhaven National Laboratory will build and deliver 20 magnets for the HL-LHC project.

    Georgio Apollinari, head of the U.S.-based effort and a scientist at Fermilab, noted that the first of these large superconducting magnets that the U.S. labs are supplying for the HL-LHC had been successfully tested in late 2019. “The second production magnet has been completed and was ready to be tested in March 2020 before the impact of COVID-19,” 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

    LBNL campus

    LBNL Molecular Foundry

    Bringing Science Solutions to the World
    In the world of science, Lawrence Berkeley National Laboratory (Berkeley Lab) is synonymous with “excellence.” Thirteen Nobel prizes are associated with Berkeley Lab. Seventy Lab scientists are members of the National Academy of Sciences (NAS), one of the highest honors for a scientist in the United States. Thirteen of our scientists have won the National Medal of Science, our nation’s highest award for lifetime achievement in fields of scientific research. Eighteen of our engineers have been elected to the National Academy of Engineering, and three of our scientists have been elected into the Institute of Medicine. In addition, Berkeley Lab has trained thousands of university science and engineering students who are advancing technological innovations across the nation and around the world.

    Berkeley Lab is a member of the national laboratory system supported by the U.S. Department of Energy through its Office of Science. It is managed by the University of California (UC) and is charged with conducting unclassified research across a wide range of scientific disciplines. Located on a 202-acre site in the hills above the UC Berkeley campus that offers spectacular views of the San Francisco Bay, Berkeley Lab employs approximately 3,232 scientists, engineers and support staff. The Lab’s total costs for FY 2014 were $785 million. A recent study estimates the Laboratory’s overall economic impact through direct, indirect and induced spending on the nine counties that make up the San Francisco Bay Area to be nearly $700 million annually. The Lab was also responsible for creating 5,600 jobs locally and 12,000 nationally. The overall economic impact on the national economy is estimated at $1.6 billion a year. Technologies developed at Berkeley Lab have generated billions of dollars in revenues, and thousands of jobs. Savings as a result of Berkeley Lab developments in lighting and windows, and other energy-efficient technologies, have also been in the billions of dollars.

    Berkeley Lab was founded in 1931 by Ernest Orlando Lawrence, a UC Berkeley physicist who won the 1939 Nobel Prize in physics for his invention of the cyclotron, a circular particle accelerator that opened the door to high-energy physics. It was Lawrence’s belief that scientific research is best done through teams of individuals with different fields of expertise, working together. His teamwork concept is a Berkeley Lab legacy that continues today.

    A U.S. Department of Energy National Laboratory Operated by the University of California.

    University of California Seal

     
  • richardmitnick 9:13 am on May 29, 2020 Permalink | Reply
    Tags: , , LBNL Lawrence Berkeley National Lab, , , The Daya Bay reactor neutrino experiment in Shenzen China has continued to pump data to remote supercomputers for analyses.   

    From Lawrence Berkeley National Lab: “Daya Bay Reactor Experiment Continues to Generate Data” 


    From Lawrence Berkeley National Lab

    May 29, 2020

    Glenn Roberts Jr.
    geroberts@lbl.gov
    (510) 520-0843

    1
    Antineutrino detectors are submersed in liquid at the Daya Bay experiment, as seen during the final phase of construction in August 2012. (Credit: Roy Kaltschmidt/Berkeley Lab)

    Daya Bay, nuclear power plant, approximately 52 kilometers northeast of Hong Kong and 45 kilometers east of Shenzhen, China
    _______________________________________
    Experiment: Daya Bay reactor neutrino experiment
    About: The Daya Bay reactor neutrino experiment is designed to measure the properties of ghostly particles called neutrinos, and more specifically reactor-produced antineutrinos.
    Location: Daya Bay Nuclear Power Plant complex, Shenzen, China.
    Role: Berkeley Lab’s Kam-Biu Luk, co-spokesperson for the Daya Bay experiment, leads U.S. participation in the experiment.
    Website: http://dayabay.ihep.ac.cn/
    _______________________________________

    Largely unaffected by the pandemic, the Daya Bay reactor neutrino experiment in Shenzen, China, has continued to pump data to remote supercomputers for analyses.

    “Since 2017, we have instituted remote shifts so that members don’t have to travel to Daya Bay for babysitting the operation of the experiment,” said Kam-Biu Luk, a co-spokesperson for the Daya Bay collaboration who is a faculty senior scientist at Berkeley Lab and a physics professor at UC Berkeley.

    “We can monitor the health of the experiment even with a cell phone. As a matter of fact, I have stopped and checked the status of the experiment with my iPhone while I was getting groceries with my wife,” he added.

    The experiment, which first launched in 2011, is designed to capture signals for nuclear reactor-produced particles known as antineutrinos that are detected by sensors in liquid-filled tanks.

    Its goal is to provide new insight about the neutrino properties – neutrinos can switch among three known varieties, known as flavors, for example, and can pass through most matter unchanged and uninterrupted. And the experiment has already contributed new findings about neutrinos.

    The Daya Bay international collaboration involves more than 200 researchers at about 40 institutions in Asia, Europe, and the U.S., and Luk noted that the collaboration is fortunate in its existing capacity for remote work. “We are used to holding meetings remotely across different time zones,” he said. “As a result, life is as usual in this regard.”

    While the absence of face-to-face discussions is a downside during this time of widespread shelter-in-place orders, Luk said that without daily car commuting to the office there is now more time to spend on the science of the experiment.

    “Many of us now can focus on computing activities and data analysis with less distraction,” he said. “Considering how disruptive this COVID-19 pandemic is to societies, it is kind of a miracle that we haven’t been negatively impacted in the data movement.”

    More:

    New Measurements Suggest ‘Antineutrino Anomaly’ Fueled by Modeling Error, April 5, 2017
    Best Precision Yet for Neutrino Measurements at Daya Bay, Sept. 11, 2015
    Announcing the First Results from Daya Bay: Discovery of a New Kind of Neutrino Transformation, March 7, 2012

    See the full article here .

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

    Please help promote STEM in your local schools.

    Stem Education Coalition

    LBNL campus

    LBNL Molecular Foundry

    Bringing Science Solutions to the World
    In the world of science, Lawrence Berkeley National Laboratory (Berkeley Lab) is synonymous with “excellence.” Thirteen Nobel prizes are associated with Berkeley Lab. Seventy Lab scientists are members of the National Academy of Sciences (NAS), one of the highest honors for a scientist in the United States. Thirteen of our scientists have won the National Medal of Science, our nation’s highest award for lifetime achievement in fields of scientific research. Eighteen of our engineers have been elected to the National Academy of Engineering, and three of our scientists have been elected into the Institute of Medicine. In addition, Berkeley Lab has trained thousands of university science and engineering students who are advancing technological innovations across the nation and around the world.

    Berkeley Lab is a member of the national laboratory system supported by the U.S. Department of Energy through its Office of Science. It is managed by the University of California (UC) and is charged with conducting unclassified research across a wide range of scientific disciplines. Located on a 202-acre site in the hills above the UC Berkeley campus that offers spectacular views of the San Francisco Bay, Berkeley Lab employs approximately 3,232 scientists, engineers and support staff. The Lab’s total costs for FY 2014 were $785 million. A recent study estimates the Laboratory’s overall economic impact through direct, indirect and induced spending on the nine counties that make up the San Francisco Bay Area to be nearly $700 million annually. The Lab was also responsible for creating 5,600 jobs locally and 12,000 nationally. The overall economic impact on the national economy is estimated at $1.6 billion a year. Technologies developed at Berkeley Lab have generated billions of dollars in revenues, and thousands of jobs. Savings as a result of Berkeley Lab developments in lighting and windows, and other energy-efficient technologies, have also been in the billions of dollars.

    Berkeley Lab was founded in 1931 by Ernest Orlando Lawrence, a UC Berkeley physicist who won the 1939 Nobel Prize in physics for his invention of the cyclotron, a circular particle accelerator that opened the door to high-energy physics. It was Lawrence’s belief that scientific research is best done through teams of individuals with different fields of expertise, working together. His teamwork concept is a Berkeley Lab legacy that continues today.

    A U.S. Department of Energy National Laboratory Operated by the University of California.

    University of California Seal

     
  • richardmitnick 11:30 am on May 22, 2020 Permalink | Reply
    Tags: , , , , , LBNL Lawrence Berkeley National Lab, The effects of the COVID pandemic   

    From Lawrence Berkeley National Lab: “DESI Team Prepares for Telescope Instrument’s Restart after Unexpected Shutdown” 


    From Lawrence Berkeley National Lab

    May 22, 2020
    Glenn Roberts Jr.
    glennemail@gmail.com
    (510) 520-0843

    Before COVID-19 hit U.S., project was on track to begin its 3D map of the universe this summer.

    The Dark Energy Spectroscopic Instrument (DESI), installed on an Arizona mountaintop, was quickly moving through its testing stages and making headway toward the start of its 5-year observing run as project participants from around the world traveled to attend a DESI collaboration meeting in Tucson, Arizona, in early March.

    LBNL/DESI spectroscopic instrument on the Mayall 4-meter telescope at Kitt Peak National Observatory started in 2018

    NOAO/Mayall 4 m telescope at Kitt Peak, Arizona, USA, Altitude 2,120 m (6,960 ft)

    Kitt Peak National Observatory of the Quinlan Mountains in the Arizona-Sonoran Desert on the Tohono O’odham Nation, 88 kilometers 55 mi west-southwest of Tucson, Arizona, Altitude 2,096 m (6,877 ft)

    But as cases of COVID-19 were mounting in the U.S. and other nations around the world, collaboration leaders acted quickly to pull the plug on the in-person meeting – planned from March 9-13, 2020 – and to transition to an online meeting.

    “We already had people in the air coming to the U.S. from all parts of the world: France, the U.K., Taiwan, and Korea,” said Michael Levi, DESI project director and a scientist at the U.S. Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab), which is the lead institution for the DESI project.

    Meeting organizers helped travelers who had already made the journey to Tucson find ways to return home before the onset of widespread travel restrictions. “No one got stranded,” Levi said. Others were able to cancel their travel plans in time. The hurriedly planned online meeting drew about 200 participants, which was actually higher than the usual in-person head count, he noted.

    At that time, it wasn’t yet clear how the spread of COVID-19 would affect daily life in the U.S., or the DESI project itself. The meeting content focused, instead, on the science that would come out of DESI. The instrument will search for new insights into dark energy, responsible for the universe’s mysteriously accelerating expansion, by measuring the light of tens of millions of galaxies to produce the most massive 3D map of the universe.

    “The meeting wasn’t about the instrument today, it was about the science tomorrow,” Levi noted. “We didn’t quite know what was in store for us. We were still figuring that out at the time.”

    But as the virtual meeting progressed, day by day it became more and more clear that the response to COVID-19 would lead to big, unforeseen changes for the U.S., and for DESI and all of its participants.

    “By March 13, the last day of the meeting, we realized we would be shutting down the instrument,” Levi said, “which we would do the following Monday. We realized we could no longer run at all.”

    In the last two days before this closure, DESI crews raced to use the instrument to capture some night-sky measurements. They succeeded in collecting the light signatures, or spectra, for about 100,000 objects in those final days, and researchers are still poring through this data.

    By March 18, crews at the Kitt Peak National Observatory site where DESI is installed had successfully shut down all of DESI’s systems. Kitt Peak is a part of the National Science Foundation’s National Optical-Infrared Astronomy Research Laboratory.

    Some of the data collected just before the shutdown would help to validate for federal reviewers that the project had completed its construction phase and was ready to begin a final testing period toward startup once it was brought online again. The federal review, which DESI passed, took place just days after the shutdown.

    Despite DESI’s shutdown, Levi said that a variety of project work is still moving forward:

    The final data release from a series of pre-DESI surveys, which will be used to help select galaxies and ultrabright objects called quasars for DESI to target, will be publicly released within a couple months. The collaboration uses supercomputers at Berkeley Lab’s National Energy Research Scientific Computing Center to process this data.
    Analysis of data that DESI has already collected during its early testing is ongoing.
    Researchers can test the systems in DESI’s high-tech focal plane, which is equipped with 5,000 swiveling robotic positioners that point fiber-optic cables at preselected sequences of galaxies and quasars, by remotely accessing a sample focal plane “wedge” at Berkeley Lab containing 500 of these positioners.
    Some hardware development is continuing. Robert Besuner, DESI project manager and a Berkeley Lab affiliate who is an engineer at UC Berkeley’s Space Sciences Laboratory, for example, has worked with other collaboration members to design and order needed components for installation on DESI. They worked on a device that is intended to prevent condensation from gathering on DESI’s lenses during this shutdown period, for example, and another to monitor air quality at the DESI site. To carry out this work, Besuner ordered parts from 3D-printing shops and other machining firms. The assembled devices were shipped to the DESI site for installation by essential workers there.
    And all DESI conversations and meetings have moved online.

    “We have considerable online and remote-work capabilities,” Levi said. “People are very industrious in getting this work done.”

    When the DESI team does receive all of the necessary approvals to proceed with the project, it will happen in stages, Levi noted.

    The first phase of DESI’s restart will involve instrument maintenance carried out by crews stationed at the Kitt Peak site, he said. In the next phase, when travel is allowed, Berkeley Lab researchers will travel to the site to turn the instrument back on.

    Then, DESI researchers will begin detailed testing of the instrument’s systems to ensure they are working as designed, and in the final phase the instrument will perform night-sky measurements again in preparation for its formal startup.

    NERSC is a DOE Office of Science user facility.

    See the full article here .

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

    Please help promote STEM in your local schools.

    Stem Education Coalition

    LBNL campus

    LBNL Molecular Foundry

    Bringing Science Solutions to the World
    In the world of science, Lawrence Berkeley National Laboratory (Berkeley Lab) is synonymous with “excellence.” Thirteen Nobel prizes are associated with Berkeley Lab. Seventy Lab scientists are members of the National Academy of Sciences (NAS), one of the highest honors for a scientist in the United States. Thirteen of our scientists have won the National Medal of Science, our nation’s highest award for lifetime achievement in fields of scientific research. Eighteen of our engineers have been elected to the National Academy of Engineering, and three of our scientists have been elected into the Institute of Medicine. In addition, Berkeley Lab has trained thousands of university science and engineering students who are advancing technological innovations across the nation and around the world.

    Berkeley Lab is a member of the national laboratory system supported by the U.S. Department of Energy through its Office of Science. It is managed by the University of California (UC) and is charged with conducting unclassified research across a wide range of scientific disciplines. Located on a 202-acre site in the hills above the UC Berkeley campus that offers spectacular views of the San Francisco Bay, Berkeley Lab employs approximately 3,232 scientists, engineers and support staff. The Lab’s total costs for FY 2014 were $785 million. A recent study estimates the Laboratory’s overall economic impact through direct, indirect and induced spending on the nine counties that make up the San Francisco Bay Area to be nearly $700 million annually. The Lab was also responsible for creating 5,600 jobs locally and 12,000 nationally. The overall economic impact on the national economy is estimated at $1.6 billion a year. Technologies developed at Berkeley Lab have generated billions of dollars in revenues, and thousands of jobs. Savings as a result of Berkeley Lab developments in lighting and windows, and other energy-efficient technologies, have also been in the billions of dollars.

    Berkeley Lab was founded in 1931 by Ernest Orlando Lawrence, a UC Berkeley physicist who won the 1939 Nobel Prize in physics for his invention of the cyclotron, a circular particle accelerator that opened the door to high-energy physics. It was Lawrence’s belief that scientific research is best done through teams of individuals with different fields of expertise, working together. His teamwork concept is a Berkeley Lab legacy that continues today.

    A U.S. Department of Energy National Laboratory Operated by the University of California.

    University of California Seal

     
  • richardmitnick 11:00 am on May 15, 2020 Permalink | Reply
    Tags: "Seeing the Universe Through New Lenses", , , , , , , , LBNL Lawrence Berkeley National Lab   

    From Lawrence Berkeley National Lab: “Seeing the Universe Through New Lenses” 


    From Lawrence Berkeley National Lab

    May 14, 2020
    Glenn Roberts Jr.
    (510) 520-0843
    geroberts@lbl.gov

    Images collected for dark energy telescope project reveal hundreds of new gravitational lens candidates.

    1
    This Hubble Space Telescope image shows a gravitational lens (center) that was first identified as a lens candidate with the assistance of a neural network that processed ground-based space images. The lens is artificially colorized and circled in this image. (Credit: Hubble Space Telescope)

    Like crystal balls for the universe’s deeper mysteries, galaxies and other massive space objects can serve as lenses to more distant objects and phenomena along the same path, bending light in revelatory ways.

    Gravitational lensing was first theorized by Albert Einstein more than 100 years ago to describe how light bends when it travels past massive objects like galaxies and galaxy clusters.

    These lensing effects are typically described as weak or strong, and the strength of a lens relates to an object’s position and mass and distance from the light source that is lensed. Strong lenses can have 100 billion times more mass than our sun, causing light from more distant objects in the same path to magnify and split, for example, into multiple images, or to appear as dramatic arcs or rings.

    The major limitation of strong gravitational lenses has been their scarcity, with only several hundred confirmed since the first observation in 1979, but that’s changing … and fast.

    A new study by an international team of scientists revealed 335 new strong lensing candidates based on a deep dive into data collected for a U.S. Department of Energy-supported telescope project in Arizona called the Dark Energy Spectroscopic Instrument (DESI).

    LBNL/DESI spectroscopic instrument on the Mayall 4-meter telescope at Kitt Peak National Observatory started in 2018

    NOAO/Mayall 4 m telescope at Kitt Peak, Arizona, USA, Altitude 2,120 m (6,960 ft)

    Kitt Peak National Observatory of the Quinlan Mountains in the Arizona-Sonoran Desert on the Tohono O’odham Nation, 88 kilometers 55 mi west-southwest of Tucson, Arizona, Altitude 2,096 m (6,877 ft)

    The study, published May 7 in The Astrophysical Journal, benefited from the winning machine-learning algorithm in an international science competition.

    “Finding these objects is like finding telescopes that are the size of a galaxy,” said David Schlegel, a senior scientist in Lawrence Berkeley National Laboratory’s (Berkeley Lab’s) Physics Division who participated in the study. “They’re powerful probes of dark matter and dark energy.”

    These newly discovered gravitational lens candidates could provide specific markers for precisely measuring distances to galaxies in the ancient universe if supernovae are observed and precisely tracked and measured via these lenses, for example.

    Strong lenses also provide a powerful window into the unseen universe of dark matter, which makes up about 85 percent of the matter in the universe, as most of the mass responsible for lensing effects is thought to be Dark Matter. Dark Matter and the accelerating expansion of the universe, driven by Dark Energy, are among the biggest mysteries that physicists are working to solve.

    In the latest study, researchers enlisted Cori, a supercomputer at Berkeley Lab’s National Energy Research Scientific Computing Center (NERSC), to automatically compare imaging data from the Dark Energy Camera Legacy Survey (DECaLS) – one of three surveys conducted in preparation for DESI – with a training sample of 423 known lenses and 9,451 non-lenses.

    NERSC Cray Cori II supercomputer at NERSC at LBNL, named after Gerty Cori, the first American woman to win a Nobel Prize in science

    The researchers grouped the candidate strong lenses into three categories based on the likelihood that they are, in fact, lenses: Grade A for the 60 candidates that are most likely to be lenses, Grade B for the 105 candidates with less pronounced features, and Grade C for the 176 candidate lenses that have fainter and smaller lensing features than those in the other two categories.

    Xiaosheng Huang, the study’s lead author, noted that the team already succeeded in winning time on the Hubble Space Telescope to confirm some of the most promising lensing candidates revealed in the study, with observing time on the Hubble that began in late 2019.

    “The Hubble Space Telescope can see the fine details without the blurring effects of Earth’s atmosphere,” Huang said.

    __________________________________________
    Dark Matter Background
    Fritz Zwicky discovered Dark Matter in the 1930s when observing the movement of the Coma Cluster., Vera Rubin a Woman in STEM denied the Nobel, did most of the work on Dark Matter.

    Fritz Zwicky from http:// palomarskies.blogspot.com

    Coma cluster via NASA/ESA Hubble

    In modern times, it was astronomer Fritz Zwicky, in the 1930s, who made the first observations of what we now call dark matter. His 1933 observations of the Coma Cluster of galaxies seemed to indicated it has a mass 500 times more than that previously calculated by Edwin Hubble. Furthermore, this extra mass seemed to be completely invisible. Although Zwicky’s observations were initially met with much skepticism, they were later confirmed by other groups of astronomers.

    Thirty years later, astronomer Vera Rubin provided a huge piece of evidence for the existence of dark matter. She discovered that the centers of galaxies rotate at the same speed as their extremities, whereas, of course, they should rotate faster. Think of a vinyl LP on a record deck: its center rotates faster than its edge. That’s what logic dictates we should see in galaxies too. But we do not. The only way to explain this is if the whole galaxy is only the center of some much larger structure, as if it is only the label on the LP so to speak, causing the galaxy to have a consistent rotation speed from center to edge.

    Vera Rubin, following Zwicky, postulated that the missing structure in galaxies is dark matter. Her ideas were met with much resistance from the astronomical community, but her observations have been confirmed and are seen today as pivotal proof of the existence of dark matter.

    Astronomer Vera Rubin at the Lowell Observatory in 1965, worked on Dark Matter (The Carnegie Institution for Science)


    Vera Rubin measuring spectra, worked on Dark Matter (Emilio Segre Visual Archives AIP SPL)


    Vera Rubin, with Department of Terrestrial Magnetism (DTM) image tube spectrograph attached to the Kitt Peak 84-inch telescope, 1970. https://home.dtm.ciw.edu

    The Vera C. Rubin Observatory currently under construction on the El Peñón peak at Cerro Pachón Chile, a 2,682-meter-high mountain in Coquimbo Region, in northern Chile, alongside the existing Gemini South and Southern Astrophysical Research Telescopes.

    LSST Data Journey, Illustration by Sandbox Studio, Chicago with Ana Kova


    __________________________________________
    Dark Energy Survey


    Dark Energy Camera [DECam], built at FNAL


    NOAO/CTIO Victor M Blanco 4m Telescope which houses the DECam at Cerro Tololo, Chile, housing DECam at an altitude of 7200 feet

    Timeline of the Inflationary Universe WMAP

    The Dark Energy Survey (DES) is an international, collaborative effort to map hundreds of millions of galaxies, detect thousands of supernovae, and find patterns of cosmic structure that will reveal the nature of the mysterious dark energy that is accelerating the expansion of our Universe. DES began searching the Southern skies on August 31, 2013.

    According to Einstein’s theory of General Relativity, gravity should lead to a slowing of the cosmic expansion. Yet, in 1998, two teams of astronomers studying distant supernovae made the remarkable discovery that the expansion of the universe is speeding up. To explain cosmic acceleration, cosmologists are faced with two possibilities: either 70% of the universe exists in an exotic form, now called dark energy, that exhibits a gravitational force opposite to the attractive gravity of ordinary matter, or General Relativity must be replaced by a new theory of gravity on cosmic scales.

    DES is designed to probe the origin of the accelerating universe and help uncover the nature of dark energy by measuring the 14-billion-year history of cosmic expansion with high precision. More than 400 scientists from over 25 institutions in the United States, Spain, the United Kingdom, Brazil, Germany, Switzerland, and Australia are working on the project. The collaboration built and is using an extremely sensitive 570-Megapixel digital camera, DECam, mounted on the Blanco 4-meter telescope at Cerro Tololo Inter-American Observatory, high in the Chilean Andes, to carry out the project.

    Over six years (2013-2019), the DES collaboration used 758 nights of observation to carry out a deep, wide-area survey to record information from 300 million galaxies that are billions of light-years from Earth. The survey imaged 5000 square degrees of the southern sky in five optical filters to obtain detailed information about each galaxy. A fraction of the survey time is used to observe smaller patches of sky roughly once a week to discover and study thousands of supernovae and other astrophysical transients.

    __________________________________________

    See the full article here .

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

    Please help promote STEM in your local schools.

    Stem Education Coalition

    LBNL campus

    LBNL Molecular Foundry

    Bringing Science Solutions to the World
    In the world of science, Lawrence Berkeley National Laboratory (Berkeley Lab) is synonymous with “excellence.” Thirteen Nobel prizes are associated with Berkeley Lab. Seventy Lab scientists are members of the National Academy of Sciences (NAS), one of the highest honors for a scientist in the United States. Thirteen of our scientists have won the National Medal of Science, our nation’s highest award for lifetime achievement in fields of scientific research. Eighteen of our engineers have been elected to the National Academy of Engineering, and three of our scientists have been elected into the Institute of Medicine. In addition, Berkeley Lab has trained thousands of university science and engineering students who are advancing technological innovations across the nation and around the world.

    Berkeley Lab is a member of the national laboratory system supported by the U.S. Department of Energy through its Office of Science. It is managed by the University of California (UC) and is charged with conducting unclassified research across a wide range of scientific disciplines. Located on a 202-acre site in the hills above the UC Berkeley campus that offers spectacular views of the San Francisco Bay, Berkeley Lab employs approximately 3,232 scientists, engineers and support staff. The Lab’s total costs for FY 2014 were $785 million. A recent study estimates the Laboratory’s overall economic impact through direct, indirect and induced spending on the nine counties that make up the San Francisco Bay Area to be nearly $700 million annually. The Lab was also responsible for creating 5,600 jobs locally and 12,000 nationally. The overall economic impact on the national economy is estimated at $1.6 billion a year. Technologies developed at Berkeley Lab have generated billions of dollars in revenues, and thousands of jobs. Savings as a result of Berkeley Lab developments in lighting and windows, and other energy-efficient technologies, have also been in the billions of dollars.

    Berkeley Lab was founded in 1931 by Ernest Orlando Lawrence, a UC Berkeley physicist who won the 1939 Nobel Prize in physics for his invention of the cyclotron, a circular particle accelerator that opened the door to high-energy physics. It was Lawrence’s belief that scientific research is best done through teams of individuals with different fields of expertise, working together. His teamwork concept is a Berkeley Lab legacy that continues today.

    A U.S. Department of Energy National Laboratory Operated by the University of California.

    University of California Seal

     
    • Barbarina Zwicky 6:10 pm on May 15, 2020 Permalink | Reply

      Rubin has been a constant nuisance to my father’s legacy in regard to Dark Matter and often took false credit for its discovery, crowning herself as “Discoverer of Dark Matter.” The naming of LSST after Rubin, is an undeserved honor for this celebrated plagiarist.

      Vera Rubin was celebrated in the press and by several institutions for her work in specific in regard to Dark Matter, my father’s discovery, as well as responsible for the roughshod over my father, his memory, and credit for his original work, by falsely assigning that credit to herself in numerous incidents involving the media and even nomenclature of her lecture: “I left Vassar and Found Dark Matter.” I consider Vera Rubin a person who attached herself to my father’s original work in parasitic forced credit, repeatedly advanced this unethical agenda and academic dishonesty, crowning herself as “Discoverer of Dark Matter,” the published achievement of another. Rubin’s dictates of conscience revealed a failed ethical compass as she assigned herself credit for my father’s methodology and that of others in the sciences in regard to the mathematical calculations in regard to the rotational speeds of galaxies, as well as claiming to be the “Discoverer of Dark Matter.” Vera Rubin was a constant unwanted barnacle that was attached to my father’s discovery, Dark Matter. The advancement of bringing the gravitational phenomena of Dark Matter to light and into the modern consciousness of physicists worldwide would have regardless been unsealed from the echoes of my father’s original work in 1933. Fritz Zwicky: “I consequently engaged in the application of certain simple general principles of morphological research, and in particular the method of Directed Intuition that would allow me to predict and visualize the existence of as yet unknown cosmic objects and phenomena.” Fritz Zwicky’s eidolon was realized from the results of his observations published in “Die Rotverschiebung von extragalaktischen Nebeln”, Helv. Phys. Acta 6, 110-127 (1933). English translation Johannes Nicolai Meyling – Barbarina Exita Zwicky (2013). Fritz Zwicky discovered Dark Matter and coined, dunkle (kalte) Materie (cold dark matter) in his 1933 article referenced above. The Mass-Radial Acceleration Discrepancy by measuring the speeds of galaxies in the Coma Cluster originated with Fritz Zwicky, not Rubin, as using the more challenging methodology of the virial theorem, by relating the total average kinetic energy and the total average potential energy of the galaxies of the Coma Cluster. He advanced that the virial for a pair of orbiting masses is zero, and used the principle of superposition to craft the argument to a system of interacting mass points. Zwicky then used the position and velocity measurements to determine the mass of the galaxy cluster. The LSST will endeavor to discover Dark Matter and should not be renamed at all, and certainly not after Vera Rubin, who plagiarized discovery in regard to Dark Matter, without acknowledgment of its provenance and pioneer, Fritz Zwicky, and deprives rightful illumination to the Father of Dark Matter. It will highlight this interloper and celebrate this forced credit from the rightful person due, Fritz Zwicky, by memorializing the name of LSST after this faux “pioneer” and self-proclaimed “Discoverer of Dark Matter.”

      Like

  • richardmitnick 11:44 am on April 1, 2020 Permalink | Reply
    Tags: "Uncertain Climate Future Could Disrupt Energy Systems", An international team of scientists has published a new study proposing an optimization methodology for designing climate-resilient energy systems., Extreme weather events – such as severe drought; storms; and heat waves – have been forecast to become more commonplace and are already starting to occur., LBNL Lawrence Berkeley National Lab   

    From Lawrence Berkeley National Lab: “Uncertain Climate Future Could Disrupt Energy Systems” 

    From Lawrence Berkeley National Lab

    Julie Chao
    JHChao@lbl.gov
    (510) 486-6491

    An international research team proposes a method to make energy systems more resilient.

    1
    Climate variability could create a gap between total energy generation and demand – a situation that could lead to blackouts. (Credit: iStock/Tomwang112)

    Extreme weather events – such as severe drought, storms, and heat waves – have been forecast to become more commonplace and are already starting to occur. What has been less studied is the impact on energy systems and how communities can avoid costly disruptions, such as partial or total blackouts.

    Now an international team of scientists has published a new study proposing an optimization methodology for designing climate-resilient energy systems and to help ensure that communities will be able to meet future energy needs given weather and climate variability. Their findings were recently published in Nature Energy.

    “On one side is energy demand – there are different types of building needs, such as heating, cooling, and lighting. Because of long-term climate change and short-term extreme weather events, the outdoor environment changes, which leads to changes in building energy demand,” said Tianzhen Hong, a Berkeley Lab scientist who helped design the study. “On the other side, climate can also influence energy supply, such as power generation from hydro, solar and wind turbines. Those could also change because of weather conditions.”

    Working with collaborators from Switzerland, Sweden, and Australia, and led by a scientist at the Ecole Polytechnique Fédérale de Lausanne (EPFL), the team developed a stochastic-robust optimization method to quantify impacts and then use the data to design climate-resilient energy systems. Stochastic optimization methods are often used when variables are random or uncertain.

    “Energy systems are built to operate for 30 or more years. Current practice is just to assume typical weather conditions today; urban planners and designers don’t commonly factor in future uncertainties,” said Hong, a computational scientist leading multi-scale energy modeling and simulation at Berkeley Lab. “There is a lot of uncertainty around future climate and weather.”

    “Energy systems,” as defined in the study, provide energy needs, and sometimes energy storage, to a group of buildings. The energy supplied could include gas or electricity from conventional or renewable sources. Such community energy systems are not as common in the U.S. but may be found on some university campuses or in business parks.

    The researchers investigated a wide range of scenarios for 30 Swedish cities. They found that under some scenarios the energy systems in some cities would not be able to generate enough energy. Notably, climate variability could create a 34% gap between total energy generation and demand and a 16% drop in power supply reliability – a situation that could lead to blackouts.

    “We observed that current energy systems are designed in a way that makes them highly susceptible to extreme weather events such as storms and heat waves,” said Dasun Perera, a scientist at EPFL’s Solar Energy and Building Physics Laboratory and lead author of the study. “We also found that climate and weather variability will result in significant fluctuations in renewable power being fed into electric grids as well as energy demand. This will make it difficult to match the energy demand and power generation. Dealing with the effects of climate change is going to prove harder than we previously thought.”

    The authors note that 3.5 billion people live in urban areas, consuming two-thirds of global energy, and by 2050 urban areas are expected to hold more than two-thirds of the world’s population. “Distributed energy systems that support the integration of renewable energy technologies will support the energy transition in the urban context and play a vital role in climate change adaptation and mitigation,” they wrote.

    Hong leads an urban science research group at Berkeley Lab that studies energy and environmental issues at the city scale. The group is part of Berkeley Lab’s Building Technology and Urban Systems Division, which for decades has been at the forefront of research into advancing energy efficiency in the built environment.

    See the full article here .

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

    Please help promote STEM in your local schools.

    Stem Education Coalition

    LBNL campus

    LBNL Molecular Foundry

    Bringing Science Solutions to the World
    In the world of science, Lawrence Berkeley National Laboratory (Berkeley Lab) is synonymous with “excellence.” Thirteen Nobel prizes are associated with Berkeley Lab. Seventy Lab scientists are members of the National Academy of Sciences (NAS), one of the highest honors for a scientist in the United States. Thirteen of our scientists have won the National Medal of Science, our nation’s highest award for lifetime achievement in fields of scientific research. Eighteen of our engineers have been elected to the National Academy of Engineering, and three of our scientists have been elected into the Institute of Medicine. In addition, Berkeley Lab has trained thousands of university science and engineering students who are advancing technological innovations across the nation and around the world.

    Berkeley Lab is a member of the national laboratory system supported by the U.S. Department of Energy through its Office of Science. It is managed by the University of California (UC) and is charged with conducting unclassified research across a wide range of scientific disciplines. Located on a 202-acre site in the hills above the UC Berkeley campus that offers spectacular views of the San Francisco Bay, Berkeley Lab employs approximately 3,232 scientists, engineers and support staff. The Lab’s total costs for FY 2014 were $785 million. A recent study estimates the Laboratory’s overall economic impact through direct, indirect and induced spending on the nine counties that make up the San Francisco Bay Area to be nearly $700 million annually. The Lab was also responsible for creating 5,600 jobs locally and 12,000 nationally. The overall economic impact on the national economy is estimated at $1.6 billion a year. Technologies developed at Berkeley Lab have generated billions of dollars in revenues, and thousands of jobs. Savings as a result of Berkeley Lab developments in lighting and windows, and other energy-efficient technologies, have also been in the billions of dollars.

    Berkeley Lab was founded in 1931 by Ernest Orlando Lawrence, a UC Berkeley physicist who won the 1939 Nobel Prize in physics for his invention of the cyclotron, a circular particle accelerator that opened the door to high-energy physics. It was Lawrence’s belief that scientific research is best done through teams of individuals with different fields of expertise, working together. His teamwork concept is a Berkeley Lab legacy that continues today.

    A U.S. Department of Energy National Laboratory Operated by the University of California.

    University of California Seal

     
  • richardmitnick 11:19 am on March 26, 2020 Permalink | Reply
    Tags: "Looking Up From the Mountaintop: Q&A With a Telescope Instrument’s Lead Observer", DESI will collect the light from about 35 million galaxies and quasars to help learn about dark energy which is driving the accelerating expansion of the universe., LBNL Lawrence Berkeley National Lab, Satya Gontcho A Gontcho, The Dark Energy Spectroscopic Instrument is housed within the Mayall Telescope dome at Kitt Peak National Observatory.   

    From Lawrence Berkeley National Lab: “Looking Up From the Mountaintop: Q&A With a Telescope Instrument’s Lead Observer” Satya Gontcho A Gontcho 

    From Lawrence Berkeley National Lab

    March 26, 2020
    Glenn Roberts Jr.
    geroberts@lbl.gov
    (510) 520-0843

    Satya Gontcho A Gontcho sets her sights high – on millions of distant galaxies and quasars that will be mapped in 3D by the Dark Energy Spectroscopic Instrument.

    1
    A view of the Mayall Telescope (tallest structure) and the Kitt Peak National Observatory site near Tucson, Arizona. The Dark Energy Spectroscopic Instrument is housed within the Mayall dome. (Credit: Marilyn Sargent/Berkeley Lab)

    LBNL/DESI spectroscopic instrument on the Mayall 4-meter telescope at Kitt Peak National Observatory started in 2018

    It’s one thing to design, assemble, and install a next-generation telescope instrument. It’s another to bring it to life.

    The Dark Energy Spectroscopic Instrument (DESI), installed on the Mayall Telescope at Kitt Peak National Observatory near Tucson, Arizona, contains more than half a million parts in one of its central components, known as a focal plane. Making sure that all of DESI’s parts work together as designed – and that it is functioning in tandem with DESI’s other components – involves a lot of testing and troubleshooting.

    2
    Satya Gontcho A Gontcho

    Satya Gontcho A Gontcho, a research associate at the University of Rochester, nearly a year ago was appointed as a lead observing scientist for DESI. She is part of the team that has helped to prepare the instrument for the start of its five-year observing run, which is slated to begin later this year. The Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab) is the lead institution in the DESI project, which is supported by a large international collaboration.

    Gontcho A Gontcho previously participated in an imaging survey in Chile that was used to help select galaxy and quasar targets for DESI. Quasars, among the brightest objects in the universe, are powered by supermassive black holes at the center of galaxies. She also worked on a predecessor experiment to DESI called BOSS, the Baryon Oscillation Spectroscopic Survey.

    BOSS Supercluster Baryon Oscillation Spectroscopic Survey (BOSS)

    DESI will collect the light from about 35 million galaxies and quasars to help learn about dark energy, which is driving the accelerating expansion of the universe. DESI could also supply new insights about the life cycle of galaxies and how the cosmic web – the large-scale structure of the universe – took shape. It will collect the galaxies’ and quasars’ light using an array of 5,000 robotic positioners that each carry a fiber-optic cable.

    Every positioner can point a fiber-optic cable at a galaxy or quasar, so DESI can capture the light of 5,000 objects at a time. The light is split up into different colors and measured by a bank of 10 instruments called spectrographs, and this data will be used to gauge galaxy distances and the rate at which they are moving away from us.

    In this Q&A, Gontcho A Gontcho shares her experiences at the Kitt Peak site, including evening observing stints to run through detailed checklists and probe how DESI’s components are working.

    ___________________________________________________________________
    Q: What is it like to work on DESI directly at the Kitt Peak site?

    A: As soon as you set foot there, it is kind of like a black hole – you get completely absorbed by the tasks at hand and time passes really quickly. At the moment, we are testing the instrument and making sure it is ready for the five-year survey. While overseeing an observing run, not every task is challenging on its own; however, there are so many things to monitor at once that you must always be alert. As a result, you need to quickly develop an understanding of what is critical and what is not.

    Most of the people who I have been working with are instrument experts in their specific areas. I have been learning a lot of things from them on the fly – everyone is incredibly helpful and collaborative and pleasant to work with.

    On the busiest days, I have seen about 15 to 17 people on-site. Most notably, there are about 30 people who are not on the mountain but are always available online and ready to help. Seeing such a large group of people working so well together when the stakes are this high – and considering the work virtually never stops – it is truly inspiring and worth taking a moment to appreciate.

    Q: What is it like to participate in an evening of observations with DESI on the mountaintop?

    3
    Satya Gontcho A Gontcho inside the Mayall Telescope dome in 2019, during her first visit to Kitt Peak. The DESI commissioning instrument is visible in the background. (Courtesy of Satya Gontcho A Gontcho.)

    A: My shifts at the Mayall Telescope are for seven nights. I wake up around 2 p.m., grab breakfast and go up to the telescope around 3:30 p.m. Then I get a rundown from the day crew who are working on instrument tuning and upgrades. At 4 p.m. I will usually welcome the new observers beginning their four-day shifts, and at 4:30 p.m. we have a teleconference with other DESI collaborators to reassess our priorities and design an observing plan for the night. Around 5 p.m. we have dinner, and by 6 p.m. we are back in the control room and ready to proceed.

    The control room is located on the middle floor of the telescope, which is essentially a huge concrete building. The fact that you don’t see much sunlight for a week can be pretty alienating.

    Most of the electronic noise in the control room comes from the warning sounds of the DESI operating system. As things progress, we’re expecting to hear those less and less! On occasion, the wind can blow very, very strongly at Kitt Peak – I’ve experienced sustained winds of 60 mph, with 90 mph gushes – and in those instances you can feel the dome vibrating all the way down to the control room several floors below.

    During a night of observing you have about four people in the control room, including a telescope operator who is a member of the OIR Lab (National Optical-Infrared Astronomy Research Laboratory) staff, and a lead observer – that’s the position I occupy. The telescope operator is in charge of the safety of the telescope, and the lead observer is in charge of the safety of the DESI instrument and running the observations.

    To kickoff our night, we start by turning on the spectrographs. We need to turn them on a minimum of 30 minutes before observations. We have cameras on all of the critical sites in the building that we need to see from the control room.

    Then we start the calibration. We point the telescope to a white screen inside the telescope dome and take test exposures. We check that everything is working as expected from the spectrographs’ point of view.

    Then we go on sky (start observing) and calibrate the guiding and focusing camera system to ensure the quality and stability of the images we will collect. When the telescope moves it is incredibly smooth –you do not feel anything or hear it.

    Collecting enough information from a particular part of the sky for our tests usually takes about two hours. Since the fall, we have been going through a list of critical things to optimize and solve.

    Q: What have you enjoyed about the experience of helping to bring DESI online?

    A: Coming here every few weeks, I have been able to see how much things have progressed from one month to another: There is a lot of hard work on the part of many, many people in order to make this survey a success, and it always shows. To contribute to this effort, while having a front-row seat to what it takes to get quality data, it has been tremendously enriching for me. It is enriching as a scientist to experience the process and to get a grasp of all of the various steps involved. But also it is enriching as a human being to experience people working together, collaborating with each other in the best way possible.

    I am being trained by literally the handful of people who have this specific expertise on Earth. It is a big privilege – a once-in-a-lifetime chance to learn from them – and for me that is tremendously exciting.

    Q: How did you become involved with the DESI project and how has your role changed since you joined?

    A: I was a postdoc in London when I joined DESI a couple of years ago. I observed for the DESI imaging survey in Chile. Before that I had been involved in the BOSS survey, specifically using quasar spectra for cosmology purposes.

    When I joined BOSS, all of the data was flowing in. At that time it seemed that the bulk of the work started there, with analyzing the data. But that was a rookie assessment. Being involved earlier in the process of getting a cosmological survey on its feet has allowed me to develop a deep appreciation for all of the work that goes on behind the scenes.

    I have been observing with DESI for one week every month since we saw first light in October. We have 10 lead observers on rotation, and half of the lead observers are also instrument experts who need to be working during the day shifts on their issues.

    4
    Satya Gontcho A Gontcho (seated, second from left) was serving as lead observer in the DESI control room on Oct. 22, 2019 – the night of DESI’s “first light,” when its 5,000 fiber-optic “eyes” were opened to the sky. Also pictured are (from left) Klaus Honscheid, Doug Williams (seated at bottom), Arjun Dey (standing with laptop), Behzad Abareshi, Connie Rockosi (seated near top), Laurent Le Guillou (hooded sweatshirt), and Bob Marshall. (Courtesy of Satya Gontcho A Gontcho)

    The next step for our research is to collect a representative subsample of the dataset we are expecting to get from the five-year survey. The priority at this stage is to test the methods that have been developed for the past few years on real DESI data to determine how far away quasars and galaxies are.

    The previous phase, called commissioning, was successful and upon restart of activities DESI will enter the survey validation phase. This represents the last stretch before operations normalize and we reach the point where everything runs as it should during the next five years.

    See the full article here .

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

    Please help promote STEM in your local schools.

    Stem Education Coalition

    LBNL campus

    LBNL Molecular Foundry

    Bringing Science Solutions to the World
    In the world of science, Lawrence Berkeley National Laboratory (Berkeley Lab) is synonymous with “excellence.” Thirteen Nobel prizes are associated with Berkeley Lab. Seventy Lab scientists are members of the National Academy of Sciences (NAS), one of the highest honors for a scientist in the United States. Thirteen of our scientists have won the National Medal of Science, our nation’s highest award for lifetime achievement in fields of scientific research. Eighteen of our engineers have been elected to the National Academy of Engineering, and three of our scientists have been elected into the Institute of Medicine. In addition, Berkeley Lab has trained thousands of university science and engineering students who are advancing technological innovations across the nation and around the world.

    Berkeley Lab is a member of the national laboratory system supported by the U.S. Department of Energy through its Office of Science. It is managed by the University of California (UC) and is charged with conducting unclassified research across a wide range of scientific disciplines. Located on a 202-acre site in the hills above the UC Berkeley campus that offers spectacular views of the San Francisco Bay, Berkeley Lab employs approximately 3,232 scientists, engineers and support staff. The Lab’s total costs for FY 2014 were $785 million. A recent study estimates the Laboratory’s overall economic impact through direct, indirect and induced spending on the nine counties that make up the San Francisco Bay Area to be nearly $700 million annually. The Lab was also responsible for creating 5,600 jobs locally and 12,000 nationally. The overall economic impact on the national economy is estimated at $1.6 billion a year. Technologies developed at Berkeley Lab have generated billions of dollars in revenues, and thousands of jobs. Savings as a result of Berkeley Lab developments in lighting and windows, and other energy-efficient technologies, have also been in the billions of dollars.

    Berkeley Lab was founded in 1931 by Ernest Orlando Lawrence, a UC Berkeley physicist who won the 1939 Nobel Prize in physics for his invention of the cyclotron, a circular particle accelerator that opened the door to high-energy physics. It was Lawrence’s belief that scientific research is best done through teams of individuals with different fields of expertise, working together. His teamwork concept is a Berkeley Lab legacy that continues today.

    A U.S. Department of Energy National Laboratory Operated by the University of California.

    University of California Seal

     
  • richardmitnick 12:07 pm on March 4, 2020 Permalink | Reply
    Tags: "Graphene: A Talented 2D Material Gets a New Gig", , , Graphene a “high-order Chern insulator”, Graphene could offer a unique advantage in the development of next-generation electronics and memory storage devices, LBNL Lawrence Berkeley National Lab, , Superconducting; insulating; and a type of magnetism called ferromagnetism.   

    From Lawrence Berkeley National Lab: “Graphene: A Talented 2D Material Gets a New Gig” 

    From Lawrence Berkeley National Lab

    March 4, 2020
    Theresa Duque
    tnduque@lbl.gov
    (510) 495-2418

    Berkeley Lab scientists tap into graphene’s hidden talent as an electrically tunable superconductor, insulator, and magnetic device for the advancement of quantum information science.

    1
    An optical image of the graphene device on a silicon dioxide/silicon chip. Shining metal wires are connected to gold electrodes for electrical measurement. (Credit: Guorui Chen/Berkeley Lab.)

    Ever since graphene’s discovery in 2004, scientists have looked for ways to put this talented, atomically thin 2D material to work. Thinner than a single strand of DNA yet 200 times stronger than steel, graphene is an excellent conductor of electricity and heat, and it can conform to any number of shapes, from an ultrathin 2D sheet, to an electronic circuit.

    Last year, a team of researchers led by Feng Wang, a faculty scientist in Berkeley Lab’s Materials Sciences Division and a professor of physics at UC Berkeley, developed a multitasking graphene device that switches from a superconductor that efficiently conducts electricity, to an insulator that resists the flow of electric current, and back again to a superconductor.

    Now, as reported in Nature today, the researchers have tapped into their graphene system’s talent for juggling not just two properties, but three: superconducting, insulating, and a type of magnetism called ferromagnetism. The multitasking device could make possible new physics experiments, such as research in the pursuit of an electric circuit for faster, next-generation electronics like quantum computing technologies.

    2
    Optical image of a trilayer graphene material sandwiched between boron nitride layers during the nanofabrication process (left); and the trilayer graphene/boron nitride device with gold electrodes (right). (Credit: Guorui Chen/Berkeley Lab.)

    “So far, materials simultaneously showing superconducting, insulating, and magnetic properties have been very rare. And most people believed that it would be difficult to induce magnetism in graphene, because it’s typically not magnetic. Our graphene system is the first to combine all three properties in a single sample,” said Guorui Chen, a postdoctoral researcher in Wang’s Ultrafast Nano-Optics Group at UC Berkeley, and the study’s lead author.

    Using electricity to turn on graphene’s hidden potential.

    Graphene has a lot of potential in the world of electronics. Its atomically thin structure, combined with its robust electronic and thermal conductivity, “could offer a unique advantage in the development of next-generation electronics and memory storage devices,” said Chen, who also worked as a postdoctoral researcher in Berkeley Lab’s Materials Sciences Division at the time of the study.

    The problem is that the magnetic materials used in electronics today are made of ferromagnetic metals, such as iron or cobalt alloys. Ferromagnetic materials, like the common bar magnet, have a north and a south pole. When ferromagnetic materials are used to store data on a computer’s hard disk, these poles point either up or down, representing zeros and ones – called bits.

    Graphene, however, is not made of a magnetic metal – it’s made of carbon.

    So the scientists came up with a creative workaround.

    3
    Illustration of the trilayer graphene/boron nitride moiré superlattice with electronic and ferromagnetic properties. (Credit: Guorui Chen/Berkeley Lab)

    They engineered an ultrathin device, just 1 nanometer in thickness, featuring three layers of atomically thin graphene. When sandwiched between 2D layers of boron nitride, the graphene layers – described as trilayer graphene in the study – form a repeating pattern called a moiré superlattice.

    By applying electrical voltages through the graphene device’s gates, the force from the electricity prodded electrons in the device to circle in the same direction, like tiny cars racing around a track. This generated a forceful momentum that transformed the graphene device into a ferromagnetic system.

    4
    Schematic of the double-gated trilayer graphene/boron nitride device. The inset shows the moiré superlattice pattern between the trilayer graphene and the bottom boron-nitride layer. (Credit: Guorui Chen/Berkeley Lab.)

    More measurements revealed an astonishing new set of properties: The graphene system’s interior had not only become magnetic but also insulating; and despite the magnetism, its outer edges morphed into channels of electronic current that move without resistance. Such properties characterize a rare class of insulators known as Chern insulators, the researchers said.

    Even more surprising, calculations by co-author Ya-Hui Zhang of the Massachusetts Institute of Technology revealed that the graphene device has not just one, but two conductive edges, making it the first observed “high-order Chern insulator,” a consequence of the strong electron-electron interactions in the trilayer graphene.

    Scientists have been in hot pursuit of Chern insulators in a field of research known as topology, which investigates exotic states of matter. Chern insulators offer potential new ways to manipulate information in a quantum computer, where data is stored in quantum bits, or qubits. A qubit can represent a one, a zero, or a state in which it is both a one and a zero at the same time.

    “Our discovery demonstrates that graphene is an ideal platform for studying different physics, ranging from single-particle physics, to superconductivity, and now topological physics to study quantum phases of matter in 2D materials,” Chen said. “It’s exciting that we can now explore new physics in a tiny device just 1 millionth of a millimeter thick.”

    The researchers hope to conduct more experiments with their graphene device to have a better understanding of how the Chern insulator/magnet emerged, and the mechanics behind its unusual properties.

    Researchers from Berkeley Lab; UC Berkeley; Stanford University; SLAC National Accelerator Laboratory; Massachusetts Institute of Technology; China’s Shanghai Jiao Tong University, Collaborative Innovation Center of Advanced Microstructures, and Fudan University; and Japan’s National Institute for Materials Science participated in the work.

    This work was supported by the Center for Novel Pathways to Quantum Coherence in Materials, an Energy Frontier Research Center funded by the U.S. Department of Energy, 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

    LBNL campus

    LBNL Molecular Foundry

    Bringing Science Solutions to the World
    In the world of science, Lawrence Berkeley National Laboratory (Berkeley Lab) is synonymous with “excellence.” Thirteen Nobel prizes are associated with Berkeley Lab. Seventy Lab scientists are members of the National Academy of Sciences (NAS), one of the highest honors for a scientist in the United States. Thirteen of our scientists have won the National Medal of Science, our nation’s highest award for lifetime achievement in fields of scientific research. Eighteen of our engineers have been elected to the National Academy of Engineering, and three of our scientists have been elected into the Institute of Medicine. In addition, Berkeley Lab has trained thousands of university science and engineering students who are advancing technological innovations across the nation and around the world.

    Berkeley Lab is a member of the national laboratory system supported by the U.S. Department of Energy through its Office of Science. It is managed by the University of California (UC) and is charged with conducting unclassified research across a wide range of scientific disciplines. Located on a 202-acre site in the hills above the UC Berkeley campus that offers spectacular views of the San Francisco Bay, Berkeley Lab employs approximately 3,232 scientists, engineers and support staff. The Lab’s total costs for FY 2014 were $785 million. A recent study estimates the Laboratory’s overall economic impact through direct, indirect and induced spending on the nine counties that make up the San Francisco Bay Area to be nearly $700 million annually. The Lab was also responsible for creating 5,600 jobs locally and 12,000 nationally. The overall economic impact on the national economy is estimated at $1.6 billion a year. Technologies developed at Berkeley Lab have generated billions of dollars in revenues, and thousands of jobs. Savings as a result of Berkeley Lab developments in lighting and windows, and other energy-efficient technologies, have also been in the billions of dollars.

    Berkeley Lab was founded in 1931 by Ernest Orlando Lawrence, a UC Berkeley physicist who won the 1939 Nobel Prize in physics for his invention of the cyclotron, a circular particle accelerator that opened the door to high-energy physics. It was Lawrence’s belief that scientific research is best done through teams of individuals with different fields of expertise, working together. His teamwork concept is a Berkeley Lab legacy that continues today.

    A U.S. Department of Energy National Laboratory Operated by the University of California.

    University of California Seal

     
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