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Vincent Y. Kotsubo, Douglas A. Bennett, Mark Croce, Michael W. Rabin, Daniel R. Schmidt, Joel N. Ullom
We have observed anomalous random telegraph noise in discrete regions of voltage bias throughout the superconducting transition in larger transition-edge sensors (TESs). The bimodal nature of these noise features is consistent with thermally activated
Matthijs Mentink, John E. Bonevich, Marc Dhalle, Daniel Dietderich, Arno Godeke, Frances Hellman, Herman Ten Kate
Binary Nb-Sn thin film samples are fabricated and characterized in terms of their composition, morphology and superconducting properties. Nb-Sn is magnetron-sputtered onto heated R-plane sapphire substrates at 700 C, 800 C, and 900 C, using a custom-built
Shmuel Barzilai, Francesca M. Tavazza, Lyle E. Levine
Gold nanowire chains are considered a good candidate for nanoelectronics devices since they exhibit remarkable structural and electrical properties. For practical engineering devices, -wurtzite BeO may be a useful platform for supporting these nanowires
Edward B. Flagg, Sergey Polyakov, Tim O. Thomay, Glenn S. Solomon
We measure the dynamics of a non-classical optical field using two-time second-order correlations in conjunction with pulsed excitation. The technique quantifies single-photon purity and coherence during the excitation-relaxation cycle of an emitter, which
Zhao Z. Deng, Alexander Smolyanitsky, Qunyang Li, Xi-Qiao Feng, Rachel J. Cannara
A negative friction coefficient is observed for graphite using atomic force microscopy. The magnitude of the friction coefficient increases with adhesion, which we control by exposing graphite to different conditions. We demonstrate that the negative
Zhao Z. Deng, Alexander Smolyanitsky, Qunyang Li, Xi-Qiao Feng, Rachel J. Cannara
We discuss a potential new measurement application based on nanotribological measurements and simulations of the model lamellar material graphite. While frictional forces always oppose motion, we have observed that friction increases with decreasing load
Leonardo M. Ranzani, Lafe F. Spietz, Jose A. Aumentado, Zoya Popovic
We present a 4 : 1 superconducting transmission-line impedance transformer for cryogenic applications. The device transforms 25 {Ω} in the coplanar waveguide to 6.25 {Ω} in the microstrip and is designed to operate at 20 mK. Calibrated measurements in a
Douglas A. Bennett, Robert D. Horansky, Daniel R. Schmidt, Andrew Hoover, Ryan Winkler, Bradley K. Alpert, James A. Beall, William B. Doriese, Joseph W. Fowler, Gene C. Hilton, Kent D. Irwin, Nathan J. Hoteling, Vincent Y. Kotsubo, John A. Mates, Galen C. O'Neil, Michael W. Rabin, Carl D. Reintsema, Francis J. Schima, Daniel S. Swetz, Leila R. Vale, Joel N. Ullom
Improvements in superconductor device fabrication, detector hybridization techniques, and superconducting quantum interference device readout have made square-centimeter-sized arrays of gammaray microcalorimeters, based on transition-edge sensors (TESs)
Valley polarization of multi-valleyed materials is of significant interest for potential applications in electronic devices. The main challenge is removing the valley degeneracy in some controllable way. The unique properties of bismuth in terms of its
Michael R. Vissers, Jiansong Gao, Jeffrey S. Kline, Martin O. Sandberg, Martin P. Weides, David S. Wisbey, David P. Pappas
The structural and electrical properties of Ti-N films deposited by reactive sputtering depend on their growth parameters, in particular the Ar:N2 gas ratio. We show that the nitrogen percentage changes the crystallographic phase of the film progressively
David L. Miller, Mark W. Keller, Justin Shaw, Ann Chiaramonti Debay, Robert Keller
Films of (111)-textured Cu, Ni, and Cu xNi y were evaluated as substrates for chemical vapor deposition of graphene. A metal thickness of 400 nm to 700 nm was sputtered onto a substrate of α–Al 2O 3(0001) at temperatures of T=250°C to 650°C. X-ray and
Since the discovery of the Amonton's law and with support of modern tribological models, friction between surfaces of three-dimensional materials is known to generally increase when the surfaces are in closer contact. Here, using molecular dynamics
The current status of experimental approaches to analyze the spin wave dynamics in ferromagnetic nanoscale structures is reviewed. Recent developments in frequency- and field swept spectroscopy to determine the resonant response of nanoscale ferromagnets
In this article, we derive an effective theory of graphene on a hexagonal boron nitride (h-BN) substrate. We show that the h-BN substrate generically opens a spectral gap in graphene despite the lattice mismatch. The origin of that gap is particularly
Matthew R. Pufall, William H. Rippard, Stephen E. Russek, Eric R. Evarts
We have measured spin-torque-driven oscillations of Ni80Fe20 free-layer nanocontacts as a function of field direction. For a given field axis angle (10◦ from the surface normal) and magnitude, simply changing the field polarity can significantly alter the
Thomas J. Silva, Justin M. Shaw, Hans T. Nembach, Dennis Rudolf, Chan La-O-Vorakiat, Marco Battiato, Roman Adam, Emrah Turgut, Stefan Mathias, Margaret M. Murnane, Henry C. Kapteyn, Claus M. Schneider
Uncovering the physical mechanisms that govern ultrafast charge and spin dynamics is crucial for understanding correlated matter as well as the fundamental limits of ultrafast spin-based electronics. Spin dynamics in magnetic materials can be driven by
William H. Butler, William Rippard, Stephen E. Russek, Ranko R. Heindl
We model "soft" error rates for writing (WSER) and for reading (RSER) for spin-torque memory devices that have a free layer with easy axis perpendicular to the film plane by solving the Fokker-Planck equation for the probability distribution of the angle
Martin O. Sandberg, Jeffrey S. Kline, Martin P. Weides, David S. Wisbey, David P. Pappas
We have investigated the correlation between the microwave loss and patterning method for coplanar waveguide titanium nitride resonators fabricated on silicon wafers. Three different methods were investigated: fluorine- and chlorine-based reactive ion
A brief review is presented that summarizes recent neutron diffuse scattering measurements on single crystal PbMg1/3Nb2/3O3 (PMN) and PbZn1/3Nb2/3O3 (PZN) doped with PbTiO3 (PT). Emphasis is placed on results that suggest that the short-range, polar
The propagation and controlled manipulation of strongly nonlinear, two-dimensional solitonic states in a thin, anisotropic ferromagnet is theoretically demonstrated. It has been recently proposed that spin polarized currents in a nanocontact device could
Martin P. Weides, Jeffrey S. Kline, Martin O. Sandberg, David P. Pappas
We present a method to systematically locate and extract capacitive and inductive losses in superconductingresonators at microwave frequencies by use of mixed-material, lumped element devices. In these devices, ultra-low loss titanium nitride was
Weilnboeck Florian, Nirav Kumar, Gottlieb Oehrlein, Ting-Ying Chung, D Graves, Mingqi Li, Eric A. Hudson, Eric C. Benck
Plasma-induced roughness development of photoresist (PR) can be due to synergistic interactions of surface modifications introduced by ions, bulk material modifications by ultraviolet (UV)/vacuum ultraviolet (VUV) radiation, and increased temperature
Douglas A. Bennett, Daniel S. Swetz, Robert D. Horansky, Daniel R. Schmidt, Joel N. Ullom
Superconducting microcalorimeters based on transition-edge sensors (TESs) are being successfully used in applications ranging from optical photon counting to gamma-ray and alpha particle spectroscopy. Practical instruments often require a complex
Francois E. Nguyen, Eva A. Zakka-Bajjani, Jose A. Aumentado, Raymond W. Simmonds
Quantum interference is an important tool for fields such as lithography, metrology and quantum processing. Two identical optical photons (photons with the same wavelength and polarization) simultaneously sent through the two input ports of a semi
Galen C. O'Neil, Peter J. Lowell, Joel N. Ullom, Jason M. Underwood
In a refrigerator, heat is moved from one system to another and this movement requires an additional dissipated power. It is desirable to both isolate the cooled system, so that its temperature may differ from the bath, and to heatsink the heated system so