The Lee Osheroff Richardson (LOR) Science Prize promotes and recognises the novel work of young scientists working in the fields of low temperatures and/or high magnetic fields in the Americas. Oxford Instruments is delighted to announce Dr Brad Ramshaw, Assistant Professor at Cornell University as the winner of the 2017 LOR Science Prize.
“I am truly honoured to have been awarded this prize. As I build my new lab in Clark Hall in the same basement where Lee, Osheroff, and Richardson did their ground-breaking work, I am continually reminded of and humbled by their legacy in low-temperature physics. Their work also reminds me that science is a collaborative effort, and I want to thank the mentors and colleagues who have made these experiments possible and who have immeasurably influenced my approach to science”, commented Ramshaw.
Dr Ramshaw is one of the most gifted young experimentalists currently active in the field of strongly correlated electron systems. Ramshaw’s technical contributions to condensed matter physics have focused on improving measurement techniques for pulsed magnetic fields up to 100 T, and on improving resonant ultrasound spectroscopy for low-temperature applications. He has applied these techniques to solve significant problems in both high-temperature and unconventional superconductivity. Most notably he has used quantum oscillation measurements to provide the first direct observation of the effects of quantum criticality on the electronic normal state of cuprate superconductors, and to determine that the Fermi surface of the cuprates is not reconstructed by magnetic order in high fields.
Researchers plumbing the mysteries of the brain gathered to share their discoveries at the inaugural Cornell Neurotech Mong Family Foundation Symposium, Sept. 29 in the Biotechnology Building.
The daylong symposium featured three of the winners of the prestigious Brain Prize – Winfried Denk, Ph.D. ’89; Karel Svoboda ’88; and David Tank, M.S. ’80, Ph.D. ’83 – all graduates of Professor Emeritus Watt Webb’s applied physics laboratory. The three built on their work in the Webb lab to develop multiphoton microscopy as an essential tool in brain research, allowing observation of minute brain structures and dynamic brain functions in real time.
Provost Michael Kotlikoff began the day with thanks for the “extraordinary generosity” of the Mong Family Foundation, guided by Stephen Mong ’92, M.Eng. ’93, MBA ’02, which enabled the university to launch Cornell Neurotech and sponsored the symposium. Cornell Neurotech’s efforts to understand how the brain produces behavior, thoughts and feelings “are vital goals with life-changing implications, and I am grateful to Stephen Mong and the Mong Family Foundation for enabling Cornell faculty and staff to strive toward them,” Kotlikoff said.
Twelve Cornell assistant professors have been awarded research grants by the Affinito-Stewart Grants Program.
The program, administered by the President’s Council of Cornell Women (PCCW), aims to increase the long-term retention of women on the Cornell faculty by supporting the completion of research important in the tenure process.
For the 2016 awards, 16 proposals were reviewed and rated by Cornell faculty members across the university and by the PCCW Grants Committee. Criteria for the review process were scholarly merit, research design, feasibility and likely relevance to promotion to tenure.
The council awarded a total of $101,615 in project funding to the 12 recipients. To honor the memory of former Cornell President Elizabeth Garrett, special mention was given this year to two grants that addressed cancer research, awarded to Pamela Chang and Gerlinde Van de Walle.
In the early 1970s, in the basement of Clark Hall, the Cornell team of professors David Lee and Robert Richardson, along with then-graduate student Douglas Osheroff, first observed superfluid helium-3. For that breakthrough, the catalyst for further research into low-temperature physics, the trio was awarded the 1996 Nobel Prize in physics.
Twenty years later, another Cornell-led team – working in that same building – has made an important discovery regarding the superconductor strontium ruthenate (Sr2RuO4,or SRO), often described as a crystalline analog of superfluid helium-3. What ties them together is the unusual way the electrons are paired together in SRO, and how the helium atoms are paired in the superfluid. That quality makes SRO intriguing for possible applications in quantum computation.
A team led by Kyle Shen, associate professor of physics, and Darrell Schlom, the Herbert Fisk Johnson Professor of Industrial Chemistry, both members of the Kavli Institute for Nanoscale Science at Cornell, has shown the ability to alter the electrical properties of the unique material through the application of strain – stretching thin films of SRO on top of a single-crystal substrate.
The group’s paper, “Strain Control of Fermiology and Many-Body Interactions in Two-Dimensional Ruthenates,” was published May 13 in Physical Review Letters.
Katja C. Nowack, assistant professor of physics in Cornell’s College of Arts and Sciences, has been selected by the Department of Energy (DOE) to receive $750,000 for research over five years as part of DOE’s Early Career Research Program for her research project, “Magnetic Imaging of Topological Phases of Matter.”
She is one of 49 scientists chosen for the grant, now in its seventh year, which intends to bolster the nation’s scientific workforce by supporting exceptional researchers during their early career years.
The prediction was that “Cooper pairs” of electrons in a superconductor could exist in two possible states. They could form a “superfluid” where all the particles are in the same quantum state and all move as a single entity, carrying current with zero resistance – what we usually call a superconductor. Or the Cooper pairs could periodically vary in density across space, a so-called “Cooper pair density wave.” For decades, this novel state has been elusive, possibly because no instrument capable of observing it existed.
Now a research team led by J.C. Séamus Davis, the James Gilbert White Distinguished Professor in the Physical Sciences, and Andrew P. Mackenzie, director of the Max-Planck Institute CPMS in Dresden, Germany, has developed a new way to use a scanning tunneling microscope (STM) to image Cooper pairs directly.
Hamidian and Edkins studied a cuprate incorporating bismuth, strontium and calcium (Bi2Sr2CaCu2O8) using an incredibly sensitive STM that scans a surface with sub-nanometer resolution, on a sample that is refrigerated to within a few thousandths of a degree above absolute zero.
At these temperatures Cooper pairs can hop across short distances from one superconductor to another, a phenomenon known as Josephson tunneling. To observe Cooper pairs, the researchers briefly lowered the tip of the probe to touch the surface and pick up a flake of the cuprate material. Cooper pairs could then tunnel between the superconductor surface and the superconducting tip. The instrument became, Davis said, “the world’s first scanning Josephson tunneling microscope.”