Direct-Current Induced Dynamics in Co90Fe10/Ni80Fe20 Point ContactsWe have directly measured coherent high-frequency magnetization dynamics in ferromagnet films induced by a spin-polarized DC current. The precession frequency can be tuned over a range of several…W. H. Rippard, M. R. Pufall, S. Kaka et al.·Sep 1, 2003SaveLearn
Finite-size scaling properties of random transverse-field Ising chains : Comparison between canonical and microcanonical ensembles for the disorderThe Random Transverse Field Ising Chain is the simplest disordered model presenting a quantum phase transition at T=0. We compare analytically its finite-size scaling properties in two different…Cecile Monthus·Sep 1, 2003SaveLearn
The relaxation dynamics of a supercooled liquid confined by rough wallsWe present the results of molecular dynamics computer simulations of a binary Lennard-Jones liquid confined between two parallel rough walls. These walls are realized by frozen amorphous…Peter Scheidler, Walter Kob, Kurt Binder·Sep 1, 2003SaveLearn
Non-equilibrium and non-linear stationary state in thermoelectric materialsEfficiency of thermoelectric materials is characterized by the figure of merit Z. Z has been believed to be a peculiar material constant. However, the accurate measurements in the present work reveal…H. Iwasaki, M. Koyano, Y. Yamamura et al.·Sep 1, 2003SaveLearn
Josephson vortices and solitons inside pancake vortex lattice in layered superconductorsIn very anisotropic layered superconductors a tilted magnetic field generates crossing vortex lattices of pancake and Josephson vortices (JVs). We study the properties of an isolated JV in the…Alexei E. Koshelev·Aug 31, 2003SaveLearn
Multi-k ConfigurationsUsing resonant x-ray scattering to perform diffraction experiments at the U M4 edge novel reflections of the generic form <kkk> have been observed in UAs0.8Se0.2 where $k = <…N. Bernhoeft, J. A. Paixão, C. Detlefs et al.·Aug 31, 2003SaveLearn
Competition between phase coherence and correlation in a mixture of Bose-Einstein condensatesTwo-species hard-core bosons trapped in a three-dimensional isotropic harmonic potential are studied with the path-integral quantum Monte Carlo simulation. The double condensates show two distinct…Hong Ma, Tao Pang·Aug 29, 2003SaveLearn
Short-range type critical behavior in spite of long-range interactions: the phase transition of a Coulomb system on a latticeOne- to three-dimensional hypercubic lattices half-filled with localized particles interacting via the long-range Coulomb potential are investigated numerically. The temperature dependences of…A. Mobius, U. K. Roessler·Aug 29, 2003SaveLearn
Heat Conduction in One-Dimensional chain of Hard Discs with Substrate PotentialHeat conduction of one-dimensional chain of equivalent rigid particles in the field of external on-site potential is considered. Zero diameters of the particles correspond to exactly integrable case…O. V. Gendelman, A. V. Savin·Aug 29, 2003SaveLearn
First-principles calculations of strontium on Si(001)This paper reports state-of-the-art electronic structure calculations on the deposition of strontium on the technologically relevant, (001) orientated silicon surface. We identified the surface…Christopher R. Ashman, Clemens J. Foerst, Karlheinz Schwarz et al.·Aug 29, 2003SaveLearn
Resonance Kondo Tunneling through a Double Quantum Dot at Finite BiasIt is shown that the resonance Kondo tunneling through a double quantum dot (DQD) with even occupation and singlet ground state may arise at a strong bias, which compensates the energy of…M. N. Kiselev, K. Kikoin, L. W. Molenkamp·Aug 29, 2003SaveLearn
Dielectric photonic crystal as medium with negative electric permittivity and magnetic permeabilityWe show that a two-dimensional photonic crystal (PC) made from a non-magnetic dielectric is a left-handed material in the sense defined by Veselago. Namely, it has negative values of both the…A. L. Efros, A. L. Pokrovsky·Aug 29, 2003SaveLearn
Lifetime of molecule-atom mixtures near a Feshbach resonance in 40KWe report a dramatic magnetic field dependence in the lifetime of trapped, ultracold diatomic molecules created through an s-wave Feshbach resonance in 40K. The molecule lifetime increases from less…C. A. Regal, M. Greiner, D. S. Jin·Aug 29, 2003SaveLearn
Oscillatory fracture path in thin elastic sheetWe report a novel mode of oscillatory crack propagation when a cutting tip is driven through a thin brittle polymer film. The phenomenon is so robust that it can easily be reproduced at hand (using…Benoit Roman, Pedro M. Reis, Basile Audoly et al.·Aug 28, 2003SaveLearn
Anomalies in the NMR of Silicon: Unexpected Spin Echoes in a Dilute Dipolar SolidNMR spin echo measurements of 29Si in Silicon powders have uncovered a variety of surprising phenomena that appear to be independent of doping. These surprises include long tails and even-odd…A. E. Dementyev, D. Li, K. MacLean et al.·Aug 27, 2003SaveLearn
Electric Field Control of Shallow Donor Impurities in SiliconWe present a tight-binding study of donor impurities in Si, demonstrating the adequacy of this approach for this problem by comparison with effective mass theory and experimental results. We consider…A. S. Martins, R. B. Capaz, Belita Koiller·Aug 27, 2003SaveLearn
Electron Dynamics in Quantum Dots on Helium SurfaceWe study single-electron quantum dots on helium surface created by electrodes submerged into the helium. The intradot potential is electrostatically controlled. We find the electron energy spectrum…M. I. Dykman, P. M. Platzman, P. Seddighrad·Aug 27, 2003SaveLearn
Option pricing and hedging with minimum local expected shortfallWe propose a versatile Monte-Carlo method for pricing and hedging options when the market is incomplete, for an arbitrary risk criterion (chosen here to be the expected shortfall), for a large class…Benoît Pochart, Jean-Philippe Bouchaud·Aug 27, 2003SaveLearn
Quantum Phase Diagram for Homogeneous Bose-Einstein CondensateWe calculate the quantum phase transition for a homogeneous Bose gas in the plane of s-wave scattering length as and temperature T. This is done by improving a one-loop result near the…Hagen Kleinert, Sebastian Schmidt, Axel Pelster·Aug 27, 2003SaveLearn
Dynamics of an anisotropic Haldane antiferromagnet in strong magnetic fieldWe report the results of elastic and inelastic neutron scattering experiments on the Haldane gap quantum antiferromagnet Ni(C5D14N2)2N3(PF6) performed at mK temperatures in a wide range of magnetic…A. Zheludev, S. M. Shapiro, Z. Honda et al.·Aug 26, 2003SaveLearn
Modeling and simulation of polycrystalline ZnO thin-film transistorsThin film transistors (TFTs) made of transparent channel semiconductors such as ZnO are of great technological importance, because their insensitivity to visible light makes device structures simple.…Faruque M. Hossain, J. Nishii, S. Takagi et al.·Aug 26, 2003SaveLearn
Field dependence of the electronic phase separation in Pr0.67Ca0.33MnO3 by small angle magnetic neutron scatteringWe have studied by small angle neutron scattering the evolution induced by the application of magnetic field of the coexistence of ferromagnetism (F) and antiferromagnetism (AF) in a crystal of…Silvana Mercone, Vincent Hardy, Christine Martin et al.·Aug 26, 2003SaveLearn
Field-induced hexagonal to square transition of the vortex lattice in overdoped La1.8Sr0.2CuO4We report on a small angle neutron scattering study of the vortex lattice in overdoped La2-xSrxCuO4 (x=0.2) up to high magnetic fields (9.5 Tesla) applied perpendicular to the CuO2 planes. At…R. Gilardi, J. Mesot, A. J. Drew et al.·Aug 26, 2003SaveLearn
Electrostatic Engineering of Nanotube Transistors for Improved PerformanceWith decreasing device dimensions, the performance of carbon nanotube field-effect transistors (CNFETs) is limited by high Off currents except at low drain voltages. We show that an asymmetric design…S. Heinze, J. Tersoff, Ph. Avouris·Aug 26, 2003SaveLearn
Hydrodynamic behavior in expanding thermal clouds of Rb-87We study hydrodynamic behavior in expanding thermal clouds of Rb-87 released from an elongated trap. At our highest densities the mean free path is smaller than the radial size of the cloud. After…I. Shvarchuck, Ch. Buggle, D. S. Petrov et al.·Aug 25, 2003SaveLearn