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Daniel R. Schmidt, Douglas A. Bennett, James P. Hays-Wehle, Daniel S. Swetz, Joel N. Ullom, Andrew Hoover, Mark Croce, Michael W. Rabin, Evelyn Bond, Terry Holesinger, Gerd Kunde, Laura Wolfsbereg
We have developed a new category of sensor for measurement of the 240Pu/239Pu mass ratio from aqueous solution samples with advantages over existing methods. Aqueous solution plutonium samples were evaporated and encapsulated inside of a gold foil absorber
Johannes Hubmayr, James A. Beall, Daniel T. Becker, Hsiao-Mei Cho, Gene C. Hilton, Dale Li, David P. Pappas, Jeffrey L. Van Lanen, Mark Devlin, Kent D. Irwin, Chris Groppi, Phillip Mauskopf
We demonstrate photon-noise limited performance at sub-millimeter wavelengths in microwave kinetic inductance detectors (MKIDs) made of a new superconducting material, a TiN/Ti/TiN trilayer film. Optical coupling is achieved by use of feedhorns, a standard
Steven W. Robey, W. Jin, D. B. Dougherty, W. G. Cullen, J. E. Reutt-Robey, J. Weeks, Q. Liu
Serpentine chain C60 phases were observed in scanning tunneling microscopy (STM) images of C60 layers on ZnPc or pentacene covered Ag(111) and Au(111) surfaces. This low density, quasi-one-dimensional organization contrasts starkly with the close-packed
Burm Baek, William H. Rippard, Matthew R. Pufall, Samuel P. Benz, Stephen E. Russek, Horst Rogalla, Paul D. Dresselhaus
Combining superconducting and magnetic materials to create novel superconducting devices has been motivated by the discovery of the Josephson critical current (Ics) oscillations with magnetic layer thickness and the demonstration of devices with switchable
Douglas A. Bennett, John A. Mates, Johnathon D. Gard, Andrew Hoover, Micheal Rabin, Carl D. Reintsema, Daniel R. Schmidt, Leila R. Vale, Joel N. Ullom
The demonstration of a microwave SQUID multiplexed readout of transition-edge sensor (TES) microcalorimeters has the potential to dramatically expand the scale of arrays of TESs. In this manuscript we discuss recent work to develop an instrument for high
John T. Vinson, Terrence J Jach, W. T. Elam, J. D. Denlinger
A comparison of the N Kα emission spectrum of crystalline ammonium nitrate to molecular orbital calculations reveals a unique observation: the peak associated with the σNO recombination is broadened so extensively as to virtually disappear. We have
We describe the results of atomistic molecular dynamics simulations of thermal rippling in graphene, obtained with a simple, low computational cost, harmonic constraint model. The constraint stiffness values are calculated directly from the bond order
Thomas J. Silva, Justin M. Shaw, Hans T. Nembach, Mathias A. Weiler
Sources of pure spin currents are a fundamental building block of spintronic devices. In ferromagnet/normal metal heterostructures, spin currents are generated at ferromagnetic resonance. This is known as spin pumping, where spin currents of both dc and ac
Yasufumi Araki, Guru S. Khalsa, Allan H. MacDonald
Disorder scattering and spin-orbit coupling are together responsible for the diffusion and relaxation of spin-density in time-reversal invariant systems. We study spin-relaxation and diffusion in a two-dimensional electron gas with Rashba spin-orbit
Thomas J. Silva, Mathias A. Weiler, Hans Nembach, Justin Shaw
The dc voltage obtained from the inverse spin Hall effect (iSHE) due to spin pumping in ferromagnet/normal-metal (NM) bilayers can be unintentionally superimposed with magnetoresistive rectification of ac charge currents in the ferromagnetic layer. We
We demonstrate a scheme to engineer the three-body interaction in circuit-QED systems by tuning a fluxonium qubit. Connecting such qubits in a square lattice and controlling the tunneling dynamics, in the form of a synthesized magnetic field, for the
Using flat-histogram Monte Carlo methods, we investigate the adsorptive behavior of the square-well fluid in two simple slit-pore- like models intended to capture fundamental characteristics of flexible adsorbent materials. The models require thermodynamic
Burm Baek, William H. Rippard, Samuel P. Benz, Stephen E. Russek, Paul D. Dresselhaus
The quantum behavior of Josephson junctions is often exploited to produce superconducting devices with outstanding performance. Josephson junctions can also be used in circuits that perform logic operations in picoseconds and may enable high-performance
Randolph E. Elmquist, Fan-Hung Liu, Lung-I Huang, Yasuhiro Fukuyama, Chi-Te Liang, Yanfei Yang
We study the quantum corrections caused by electron-electron (e-e) interactions and localization to the conductivity in few-layer epitaxial graphene, in which the carriers responsible for transport are massive. Our results demonstrate that the diffusive
Marco Manzoni, Florentin Reiter, Jacob Taylor, Anders Sorensen
In analogy with electronic transistors, a single photon transistor is a device where the presence or absence of a single gate photon controls the propagation of a large number of signal photons [1, 2]. Such devices would represent a milestone in our
Guangjun Cheng, Brent A. Sperling, James E. Maslar, Curt A. Richter, Angela R. Hight Walker
We present an investigation on tearing and scrolling of the transferred graphene on a Si/SiO2 substrate. Graphene grown by chemical vapor deposition (CVD) is transferred onto a Si/SiO2 substrate using a wet polymer-mediated process. Upon the removal of
We report parametric excitation of magnetic precession modes in nanodisks using a parallel pumping configuration. The excitations are detected using a ferromagneitc resonance force microscopy method, and the parallel-pumped spectra reveal nonlinear
James A. Beall, Dan Becker, Justus Brevik, Hsiao-Mei Cho, Gene C. Hilton, Kent D. Irwin, Dale Li, David P. Pappas, Jeffrey L. Van Lanen, Johannes Hubmayr
We are developing arrays of kinetic inductance detectors for sub-millimeter polarimetry that will be deployed on the BLAST balloon-borne instrument. The array is feedhorn-coupled, and each pixel contains two lumped-element kinetic inductance detectors
William H. Rippard, Stephen E. Russek, Matthew R. Pufall
Excited magnetization dynamics in a spin-valve device consisting of an in-plane polarizer and an out-of-plane free layer were studied numerically. In the case where the free layer is assumed to lack any in-plane anisotropy components, a finite external
Steven W. Robey, Xianjie Liu, Yinying Wei, Janice E. Reutt-Robey
The molecular organization in layers of a polar phthalocyanine, titanyl phthalocyanine (TiOPc), on the Ag(110) surface was studied with scanning tunneling microscopy (STM). TiOPc molecules adsorb on Ag(110) in a tilted configuration in contrast to the flat
Jiansong Gao, Michael R. Vissers, Martin O. Sandberg, Dale Li, Hsiao-Mei Cho, Clint Bockstiegel, Ben Mazin, Henry G. Leduc, Saptarshi Chaudhuri, David P. Pappas, K D. Irwin
We have experimentally explored and carefully characterized the important properties of TiN, including the resistivity, nonlinear kinetic inductance, the anomalous electro-dynamical response, and the two-level-system induced frequency shift and noise. We
Thomas J. Silva, Justin M. Shaw, Hans T. Nembach, Mike Mallary, Kumar Srinivasan, Gerado Bertero, Dan Wolf, Christian Kaiser, Michael Chaplin, Mahendra Pakala, Leng Qunwen, Yiming Wang, Carl Elliot, Lui Francis
A specific design for Microwave Assisted Magnetic Recording (MAMR) at about 3Tb/in 2 (0.47 Tb/cm 2 or 4.7 Pb/m 2) is discussed in detail to highlight the challenges of MAMR and to contrast its requirements with conventional Perpendicular Magnetic Recording
Thomas J. Silva, Mathias A. Weiler, Hans T. Nembach, Justin M. Shaw
In a recent Letter, Hahn et al. reported on the detection of an ac voltage in a yttrium iron garnet (YIG)/platinum (Pt) bilayer under the condition of parametrically excited resonance. The authors observe an ac voltage at the frequency of the magnetization
Douglas A. Bennett, Daniel R. Schmidt, Daniel S. Swetz, Joel N. Ullom
The fundamental mechanism of resistance in voltage-biased superconducting films is poorly understood despite its importance as the basis of transition-edge sensors (TESs). TESs are utilized in state-of- the-art microbolometers and microcalorimeters