U.S. flag

An official website of the United States government

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

Physics

Condensed matter

Search Publications

Search Title, Abstract, Conference, Citation, Keyword or Author
  • Published Date
Displaying 1001 - 1025 of 1253

Band Structure of ABC-Stacked Graphene Trilayers

July 9, 2010
Author(s)
Fan Zhang, Bhagawan Sahu, Hongki Min, Allan H. MacDonald
The ABC-stacked N-layer-graphene family of two-dimensional electron systems is described at low energies by two remarkably flat bands with Bloch states that have strongly momentum-dependent phase differences between carbon \pi-orbital amplitudes on

Adiabatic Preparation of Many-Body States in Optical Lattices

June 22, 2010
Author(s)
James V. Porto, Anders Sorensen, Ehud Altman, Michael Gullans, Mikhail Lukin, Eugene Demler
We analyze a technique for the preparation of low entropy many-body states of atoms in optical lattices based on adiabatic passage. In particular, we show that this method allows preparation of strongly correlated states as stable highest energy states of

Observation of Transparency of Erbium-doped Silicon nitride in photonic crystal nanobeam cavities

June 14, 2010
Author(s)
Yiyang Gong, Maria Makarova, Selcuk Yerci, Rui Li, Martin Stevens, Burm Baek, Sae Woo Nam, Luca Dal Negro, Jelena Vuckovic
One dimensional nanobeam photonic crystal cavities are fabricated in an Er-doped amorphous silicon nitride layer. Photoluminescence from the cavities around 1.54 mm is studied at cryogenic and room temperatures at different optical pump powers. The

Effects of disorder and internal dynamics on vortex wall propagation

May 26, 2010
Author(s)
Hongki Min, Robert D. McMichael, Michael J. Donahue, Jacques Miltat, Mark D. Stiles
Experimental measurements of domain wall propagation are typically interpreted by comparison to ideal models that ignore the effects of extrinsic disorder and the internal dynamics of domain wall structures. Using micromagnetic simulations we study vortex

Modification of edge mode dynamics of oxidized Ni 80 Fe 20 thin film edges

May 20, 2010
Author(s)
Meng Zhu, Robert D. McMichael
We use ''edge mode'' ferromagnetic resonance (FMR) to probe the magentic properties of oxidized Ni 80Fe 20 (Py) nanostripe edges. The oxidation is carried out using either oxygen plasma or thermal annealing in an oxygen ambient. We find that for both

Effect of strain, magnetic field and field angle on the critical current density of YBa 2 Cu 3 O 7-d coated conductors

May 18, 2010
Author(s)
Daniel C. van der Laan, J. F. Douglas, John (Jack) W. Ekin, Loren F. Goodrich, Theodore C. Stauffer, Cameron C. Clickner
A large, magnetic-field-dependent, reversible reduction in critical current density with axial strain in YBa 2Cu 3O 7-δ coated conductors at 75.9 K has been measured. This effect may have important implications for the performance of YBa 2Cu 3O 7-δ coated

Quasiparticle Density of States Measurements in Clean Superconducting AlMn Alloys

May 6, 2010
Author(s)
Galen C. O'Neil, Daniel R. Schmidt, Nathan A. Tomlin, Joel N. Ullom
Aluminum doped with Manganese (AlMn) forms a superconducting alloy with the transition temperature suppressed by the added Manganese. We present quasiparticle density of states measurements on superconducting AlMn alloys made by current-voltage

Code-division SQUID multiplexing

April 23, 2010
Author(s)
Michael D. Niemack, Kent D. Irwin, Joern Beyer, Hsiao-Mei Cho, William B. Doriese, Gene C. Hilton, Carl D. Reintsema, Daniel R. Schmidt, Joel N. Ullom, Leila R. Vale
Multiplexed superconducting quantum interference device (SQUID) readout systems are a critical technology for measuring large arrays of superconducting transition-edge sensor (TES) detectors. Current successful SQUID multiplexing architectures are

Origin of Electric Field Induced Magnetization in Multiferroic HoMnO 3

April 7, 2010
Author(s)
Benjamin Ueland, Jeffrey W. Lynn, Mark Laver, Y. J. Choi, S.-W. Cheong
We have performed polarized and unpolarized small angle neutron scattering experiments on single crystals of HoMnO 3 and have found that an increase in magnetic scattering at low momentum transfers begins upon cooling through temperatures close to the spin

Interference of Single Photons from Two Separate Semiconductor Quantum Dots

April 1, 2010
Author(s)
Edward B. Flagg, Andreas Muller, Sergey V. Polyakov, Alexander E. Ling, Glenn S. Solomon
We demonstrate and characterize interference between discrete photons emitted by two separate semiconductor quantum dot states in different samples excited by a pulsed laser. Their energies are tuned into resonance using strain. The photons have a total

Characterization of Soluble Anthradithiophene Derivatives

March 18, 2010
Author(s)
Brad Conrad, Calvin Chan, Marsha A. Loth, John E. Anthony, David J. Gundlach
We will discuss the growth and electrical measurements of a newly developed, partially fluorinated anthradithiophene (F-ADT) derivative with tert-butyldiphenylsilyl (TBDMS) side groups. Single crystals of the material can be readily grown and device hole

Vertically Graded Anisotropy in Co/Pd Multilayers

March 8, 2010
Author(s)
Brian J. Kirby, Joseph E. Davies, Kai Liu, Shannon Watson, G. T. Zimanyi, Robert D. Shull, Paul A. Kienzle, Julie A. Borchers
It has been theoretically predicted that depth-grading the magnetic anisotropy in perpendicular magnetic media should reduce the field required to write data, without affecting the thermal stability. To study this prediction, we have produced a series of

Energy dissipation of highly charged ions on Al oxide films

March 3, 2010
Author(s)
Joshua M. Pomeroy, Russell Lake, C E. Sosolik
Slow highly charged ions carry a large amount of potential energy that can be dissipated within femtoseconds upon interaction with a surface. HCI-insulator collisions result in high sputter yields and surface nano-feature creation due to strong coupling

Normal-state conductance used to probe superconducting tunnel junctions for quantum computing

March 3, 2010
Author(s)
David P. Pappas, Jeffrey S. Kline, Seongshik Ohy, Carlos Chapraro, Richard Bavier, Yong Kim, Eunyoung Kim
Here we report normal-state conductance measurements of three different types of superconducting tunnel junctions that are being used or proposed for quantum computing applications: p-Al/a-AlO/p-Al, e-Re/e-AlO/p-Al, and e-V/e-MgO/p-V, where p stands for

Coexisting Magnetic Order and Cooperative Paramagnetism in the Stuffed Pyrochlore Tb 2+x Ti 2-2x Nb x O 7

February 18, 2010
Author(s)
Benjamin Ueland, Jason S. Gardner, A. J. Williams, M. L. Dahlberg, J.G. Kim, Yiming Qiu, John R. Copley, P. Schiffer, R J. Cava
Neutron scattering and magnetization measurements have been performed on the stuffed pyrochlore system Tb 2+xTi 2-2xNb xO 7. We find that despite the introduction of chemical disorder and increasingly antiferromagnetic interactions, cooperative

Optimization of spin-valve parameters for magnetic bead trapping and manipulation

February 6, 2010
Author(s)
Wendy R. Altman, John M. Moreland, Stephen E. Russek, Victor M. Bright
Magneto-optic Kerr effect (MOKE) and magnetoresistance (MR) measurements were used to measure the switching characteristics of spin-valve (SV) arrays currently being developed to trap and release superparamagnetic beads within a fluid medium. The effect of

Spin-transfer dynamics in spin valves with out-of-plane magnetized CoNi free layers

January 29, 2010
Author(s)
William H. Rippard, Alina M. Deac, Matthew R. Pufall, Justin M. Shaw, Mark W. Keller, Stephen E. Russek, Gerrit E. Bauer, Claudio Serpico
We have measured spin-transfer-induced dynamics in magnetic nanocontact devices having a perpendicularly magnetized Co/Ni free layer and an in-plane magnetized CoFe fixed layer. The frequencies and powers of the excitations agree well with the predictions

Phase Diagram of Magnetic Nanodisks measured by SEMPA

January 20, 2010
Author(s)
Seok-Hwan Chung, Robert D. McMichael, Daniel T. Pierce, John Unguris
We use Scanning Electron Microscopy with Polarization Analysis (SEMPA) to image the magnetic domain structures of individual ferromagnetic nanodisks with different diameters and thicknesses, and thereby determine the phase diagram of the magnetic ground
Was this page helpful?