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We develop a set of computationally efficient and accurate interatomic interactions for an atomistic simulation of the properties of graphene on nickel surface. The approach is based on the modified embedded atom method (MEAM) for the C-C and Ni-Ni
Kai Li, Pradeep Namboodiri, Sumanth B. Chikkamaranahalli, Gheorghe Stan, Ravikiran Attota, Joseph Fu, Richard M. Silver
Micro scale features are fabricated on Si (100) surfaces using lithographic techniques and then thermally processed in an ultra high vacuum (UHV) environment. Samples are flash heated at 1200 °C and further annealed at 1050 °C for 18 hours. The surface
We used perpendicular ferromagnetic resonance to measure the damping parameter in Co 90Fe 10/Ni multilayers over a wide range of layer thicknesses. The magnetic anisotropy within this range varied from in-pane to out-of-plane. We measured (Co 90Fe 10) xNi
Jiansong Gao, Kent D. Irwin, Gene C. Hilton, John A. Mates, Daniel R. Schmidt, Leila R. Vale, Konrad W. Lehnert, Francois Mallet, Jonas Zmuidzinas
We report noise measurement of superconducting micro-resonators with a Josephson parametric amplifier. These resonators show significant amount of frequency noise caused by surface two-level systems. However, in the dissipation quadrature, no excess noise
Loren F. Goodrich, Najib Cheggour, Xifeng Lu, Jolene D. Splett, Theodore C. Stauffer, Bernard J. Filla
We have defined a rigorous and reliable method for determining the irreversible strain limit of Nb 3Sn wires. The critical current (I c) is measured as a function of applied longitudinal strain (ε), I c(ε), at one magnetic field and a temperature of 4.0 K
The electrical conductance of magnetic tunnel junction (MTJ) devices whose ultra-thin aluminum oxide tunnel barrier was irradiated by highly charged ions (HCIs) increases linearly with the fluence of HCIs, while retaining a current-voltage relationship
A suitable optical lattice for cold atoms could produce a large effective magnetic field in which the atoms would realize analogs to quantum Hall states.
Ian B. Spielman, Jay Sau, Rajdeep Sensarma, Stephen Powell, Sankar Das Sarma
Spin-orbit coupling is an important ingredient in many recently discovered phenomena such as the spin-Hall effect and topological insulators. Of particular interest is topological superconductivity, with its potential application in topological quantum
S Ghosh, H. D. Zhou, L. Balicas, Jason S. Gardner, Yiming Qiu, C. R. Wiebe
The low temperature behaviour of single crystalline SrHo 2O 4 has been characterized by DC mag- netic susceptibility, heat capacity, and neutron scattering experiments. Our results show that despite the lack of magnetic long-ranged ordering in the presence
The trend in using ultracold atoms as simulators of condensed-matter and many-body phenomena is gaining momentum. These systems can now be used to simulate quantum magnetism.
Kevin C. Wright, Anand Ramanathan, Sergio R. Muniz, Wendell Hill, Kristian Helmerson, William D. Phillips, Gretchen K. Campbell, Christopher Lobb
We have created a long-lived (40 s) persistent current in a toroidal Bose-Einstein condensate held in an all-optical trap. A repulsive optical barrier creates a tunable weak link in the condensate circuit, which can affect the current around the loop
Shannon B. Hill, Fardina Asikin, Lee J. Richter, Steven E. Grantham, Charles S. Tarrio, Thomas B. Lucatorto, Sergiy Yulin, Mark Schurmann, Viatcheslav Nesterenko, Torsten Feigl
We report on optics contamination rates induced by exposure to broad-bandwidth, high-intensity EUV radiation peaked near 8 nm in a new beamline at the NIST synchrotron. The peak intensity of 50 mW/mm2 allows extension of previous investigations of
This article presents a brief review of some of the many insights gained about metallic ferromagnetism using spin-polarized electrons as probes. Aspects of metallic ferromagnetism discussed include spin-dependent electronic structure, spin-dependent mean
Eric L. Shirley, Vinson T. John, John J. Rehr, Joshua J. Kas
We present a hybrid approach for GW/Bethe-Salpeter Equation (BSE) calculations of core excitation spectra, including x-ray absorption (XAS), electron energy loss spectra (EELS), and nonresonant inelastic x-ray scattering (NRIXS). The method is based on ab
Daniel C. van der Laan, Xifeng Lu, Loren F. Goodrich
Bundling high-temperature superconductors together to form high current cables is required in, for instance, power transmission and low-inductance magnet applications. Cabling techniques that have been applied so far have not resulted in compact
David P. Pappas, Michael R. Vissers, David S. Wisbey, Jeffrey S. Kline, Jiansong Gao
High quality factor, i.e. low loss, resonators are important for quantum information storage and addressing. In this work we study the resonance frequency and loss in superconducting coplanar waveguide resonators as a function of temperature and power. We
Ian B. Spielman, Gediminas Juzeliunas, Julius Ruseckas, Daniel Campbell
We study the center of mass of motion of cold atoms affected by laser beams. The beams couple three atomic internal states to another two states to form a double tripod scheme. By properly choosing the amplitudes and phases of the laser fields the atom
Daniel C. van der Laan, J. F. Douglas, Cameron C. Clickner, Theodore C. Stauffer, Loren F. Goodrich, Hans J. van Eck
It is well known that the critical temperature of cuprate- and iron-based high-temperature superconductors changes with pressure. YBa 2Cu 3O 7-δ coated conductors, as well as Bi 2Sr 2CaCu 2O x and Bi 2Sr 2Ca 2Cu 3O x tapes and wires, show a clear
Ian B. Spielman, Nathan Goldman, Indubala I. Satija, Predrag Nikolic, Alejandro Bermudez, Miguel A. Martin-Delgado, Maciej Lewenstein
Topological insulators are a broad class of unconventional states that respect all symmetries of the system, but have non-trivial transport and topological properties which cannot be defined locally. Until recently, all known realizations of these phases
Eduard Rocas, Juan C. Collado Gomez, Jordi Mateu, Nathan D. Orloff, James C. Booth
This work proposes a modeling method to simulate how temperature rise, due to power dissipation, affects the performance of a HTS limiter. The spatial temperature rise distribution across and along a HTS transmission line is determined by heat generation
Michael Vissers, Jiansong Gao, David S. Wisbey, David P. Pappas, C. C. Tsuei, A. D. Corcoles, Matthias Steffen
Thin films of TiN were sputter-deposited onto Si and sapphire wafers with and without SiN buffer layers. The films were fabricated into RF coplanar waveguide resonators, and internal quality factor measurements were taken at millikelvin temperatures in
Greg Stiehl, Hsiao-Mei Cho, Gene C. Hilton, Kent D. Irwin, John A. Mates, Carl D. Reintsema, Barry L. Zink
We have developed time-division SQUID multiplexers to read out large arrays of transition-edge sensor (TES) detectors. These multiplexers are used in many applications that require exquisite control of systematic error. One important application is the
Eric L. Shirley, H. K. Mao, Yang Ding, Peter Eng, Yong Q. Cai, Paul Chow, Yuming Xiao, Jinfu Shu, Russell J. Hemley, Chichang Kao, Wendy L. Mao
At high pressures, helium crystallizes as a unique insulator with the widest known electronic band gap. However, in the vicinity of the band gap and above, electronic excitations have been previously inaccessible to direct measurements. Using an optimized