Heat current in parametric quantum pumpWe investigate the heat flow in the parametric quantum pump. Using the time dependent scattering matrix theory, we have developed a general theory for the pumped heat current at finite pumping…Baigeng Wang, Jian Wang·Apr 3, 2002SaveLearn
Elusive physical electron propagator in QED-like effective theoriesWe study the previously conjectured form of the physical electron propagator and its allegedly Luttinger type of behavior in the theory of the pseudogap phase of high-temperature copper-oxide…D. V. Khveshchenko·Apr 2, 2002SaveLearn
Quantum Monte Carlo study of the 3D attractive Hubbard modelWe study the three-dimensional (3D) attractive Hubbard model by means of the Determinant Quantum Monte Carlo method. This model is a prototype for the description of the smooth crossover between BCS…A. Sewer, X. Zotos, H. Beck·Apr 2, 2002SaveLearn
Collective excitation frequencies and vortices of a Bose-Einstein condensed state with gravity-like interatomic attractionWe study the collective excitations of a neutral atomic Bose-Einstein condensate with gravity-like 1/r interatomic attraction induced by electromagnetic wave. Using the time-dependent variational…Tarun Kanti Ghosh·Apr 1, 2002SaveLearn
Non-Analytic Vertex Renormalization of a Bose Gas at Finite TemperatureWe derive the flow equations for the symmetry unbroken phase of a dilute 3-dimensional Bose gas. We point out that the flow equation for the interaction contains parts which are non-analytic at the…Georgios Metikas, Gernot Alber·Mar 31, 2002SaveLearn
Loading of a cold atomic beam into a magnetic guideWe demonstrate experimentally the continuous and pulsed loading of a slow and cold atomic beam into a magnetic guide. The slow beam is produced using a vapor loaded laser trap, which ensures…P. Cren, C. F. Roos, A. Aclan et al.·Mar 29, 2002SaveLearn
Anticipating the response of excitable systems driven by random forcingWe study the regime of anticipated synchronization in unidirectionally coupled model neurons subject to a common external aperiodic forcing that makes their behavior unpredictable. We show…M. Ciszak, O. Calvo, C. Masoller et al.·Mar 28, 2002SaveLearn
Parametric electron pumping through a quantum dot in the Kondo regimeWe report a theoretical analysis of parametric electron pump through a quantum dot in the Kondo regime. In the adiabatic regime, we have derived the expression for pumped current in the Kondo regime…Baigeng Wang, Jian Wang·Mar 28, 2002SaveLearn
Ferromagnetism in laser deposited anatase Ti1-xCoxO2-δ filmsPulsed laser deposited films of Co doped anatase TiO2 are examined for Co substitutionality, ferromagnetism, transport, magnetotransport and optical properties. Our results show limited solubility…S. R. Shinde, S. B. Ogale, S. Das Sarma et al.·Mar 27, 2002SaveLearn
Renormalization group and nonequilibrium action in stochastic field theoryWe investigate the renormalization group approach to nonequilibrium field theory. We show that it is possible to derive nontrivial renormalization group flow from iterative coarse graining of a…Juan Zanella, Esteban Calzetta·Mar 27, 2002SaveLearn
Magnetic field effect on the dielectric constant of glasses: Evidence of disorder within tunneling barriersThe magnetic field dependence of the low frequency dielectric constant er(H) of a structural glass a - SiO2 + xCyHz was studied from 400 mK to 50 mK and for H up to 3T. Measurement of both the…J. Le Cochec, F. Ladieu, P. Pari·Mar 27, 2002SaveLearn
Expected Shortfall and BeyondFinancial institutions have to allocate so-called "economic capital" in order to guarantee solvency to their clients and counter parties. Mathematically speaking, any methodology of…Dirk Tasche·Mar 27, 2002SaveLearn
Method for monopole creation in spinor Bose-Einstein condensatesWe present a method for creating a monopole in an antiferromagnetic spin-1 Bose-Einstein condensate. The required phase engineering of the multicomponent condensate is achieved using light shifts,…D. E. Chang·Mar 27, 2002SaveLearn
Laterally-doped heterostructures for III-N lasing devicesTo achieve a high-density electron-hole plasma in group-III nitrides for efficient light emission, we propose a planar two-dimensional (2D) p-i-n structure that can be created in selectively-doped…S. M. Komirenko, K. W. Kim, V. A. Kochelap et al.·Mar 27, 2002SaveLearn
Enhancement of hole injection for nitride-based light-emitting devicesA novel device design is proposed for a strong enhancement of hole injection current in nitride-based light-emitting heterostructures. Preliminary calculations show orders of magnitude increase in…S. M. Komirenko, K. W. Kim, V. A. Kochelap et al.·Mar 27, 2002SaveLearn
Quantum fluctuations of charge and phase transitions of a large Coulomb-blockaded quantum dotWe analyze ground-state properties of a large gated quantum dot coupled via a quantum point contact to a reservoir of one-dimensional interacting spinless electrons. We find that the classical…Eugene B. Kolomeisky, Robert M. Konik, Xiaoya Qi·Mar 27, 2002SaveLearn
Magneto-chiral scattering of light: a new optical manifestation of chiralityWe have investigated multiple scattering of light in systems subject to magneto-chiral (MC) effects. Our medium consists of magneto-optically active dipoles placed in a chiral geometry under the…F. A. Pinheiro, B. A. van Tiggelen·Mar 27, 2002SaveLearn
Origin and Properties of the Gap in the Half-Ferromagnetic Heusler AlloysWe study the origin of the gap and the role of chemical composition in the half-ferromagnetic Heusler alloys using the full-potential screened KKR method. In the paramagnetic phase the C1b…I. Galanakis, P. H. Dederichs, N. Papanikolaou·Mar 26, 2002SaveLearn
Surface Half-Metallicity of CrAs in the Zinc-Blende StructureThe development of new techniques such as the molecular beam epitaxy have enabled the growth of thin films of materials presenting novel properties. Recently it was made possible to grow a CrAs…I. Galanakis·Mar 26, 2002SaveLearn
Measurement induced quantum-classical transitionA model of an electrical point contact coupled to a mechanical system (oscillator) is studied to simulate the dephasing effect of measurement on a quantum system. The problem is solved at zero…D. Mozyrsky, I. Martin·Mar 26, 2002SaveLearn
Two-electron correlated motion due to Coulomb repulsionA Hubbard-type model is derived from the microscopic Schrödinger equation. We found that additional terms describing direct two-electron transitions must be added to the standard Hubbard Hamiltonian.…S. A. Gurvitz·Mar 26, 2002SaveLearn
Ballistic Spin Injection and Detection in Fe/Semiconductor/Fe JunctionsWe present ab initio calculations of the spin-dependent electronic transport in Fe/GaAs/Fe and Fe/ZnSe/Fe (001) junctions simulating the situation of a spin-injection experiment. We follow a…Phivos Mavropoulos, Olaf Wunnicke, Peter H. Dederichs·Mar 26, 2002SaveLearn
Dynamical Behavior of a Squid Ring Coupled to a Quantized Electromagnetic FieldIn this paper we investigate the dynamical behavior of a SQUID ring coupled to a quantized single-mode electromagnetic field. We have calculated the eigenstates of the combined fully quantum…R. Migliore, A. Messina·Mar 26, 2002SaveLearn
New Class of Solvable and Integrable Many-Body ModelsIntegrability conditions for systems of bosons or fermions with seniority conserving hamiltonians are derived. The conditions are shown to be invariant under a large class of transformations of the…R. W. Richardson·Mar 26, 2002SaveLearn
A continuum description of the energetics and evolution of stepped surfaces in strained nanostructuresAs a departure from existing continuum approaches for describing the stability and evolution of surfaces of crystalline materials, this article provides a description of surface evolution based on…V. B. Shenoy, L. B. Freund·Mar 25, 2002SaveLearn