2008

Exact treatment of exciton-polaron formation by Diagrammatic Monte Carlo

Evgeni Burovski 1, Holger Fehske 2, Andrei S. Mishchenko 3, 4 Physical Review Letters 101 (2008) 116403 We develop an approximation-free Diagrammatic Monte Carlo technique to study fermionic particles interacting with each other simultaneously through both an attractive Coulomb potential and bosonic excitations of the underlying medium. Exemplarily we apply the method to the long-standing exciton-polaron problem and present numerically exact results

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Exact Minimum Eigenvalue Distribution of an Entangled Random Pure State

Satya N. Majumdar 1, Oriol Bohigas 1, Arul Lakshminarayan 2, 3 Journal of Statistical Physics 131 (2008) 33-49 A recent conjecture regarding the average of the minimum eigenvalue of the reduced density matrix of a random complex state is proved. In fact, the full distribution of the minimum eigenvalue is derived exactly for both the cases of a random real and a

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Exact distribution of the maximal height of watermelons

Gregory Schehr 1, Satya N. Majumdar 2, Alain Comtet 2, Julien Randon-Furling 2 Physical Review Letters 101 (2008) 150601 We study p non intersecting one-dimensional Brownian walks, either excursions (p-watermelons with a wall) or bridges (p-watermelons without wall). We focus on the maximal height H_p of these p-watermelons configurations on the unit time interval. Using path integral techniques associated to corresponding models of

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Equation of state and effective mass of the unitary Fermi gas in a 1D periodic potential

Gentaro Watanabe 1, 2, Giuliano Orso 3, Franco Dalfovo 4, Lev P. Pitaevskii 5, 6, Sandro Stringari 7 Physical Review A: Atomic, Molecular and Optical Physics 78 (2008) 063619 By solving the Bogoliubov — de Gennes equations at zero temperature, we study the effects of a one-dimensional optical lattice on the behavior of a superfluid Fermi gas at unitarity. We show that, due to the lattice, at

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Entropic effects in the very-low-temperature regime of diluted Ising spin glasses with discrete couplings

Thomas Jorg 1, Federico Ricci-Tersenghi 2, 3 Physical Review Letters 100 (2008) 177203 We study link-diluted $\pm J$ Ising spin glass models on the hierarchical lattice and on a three-dimensional lattice close to the percolation threshold. We show that previously computed zero temperature fixed points are unstable with respect to temperature perturbations and do not belong to any critical line

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Dynamics of Annihilation II: Fluctuations of Global Quantities

P. Maynar 1, 2, M. I. Garcia de Soria 3, G. Schehr 1, A. Barrat 1, E. Trizac 3 Physical Review E: Statistical, Nonlinear, and Soft Matter Physics 77 (2008) 051128 We develop a theory for fluctuations and correlations in a gas evolving under ballistic annihilation dynamics. Starting from the hierarchy of equations governing the evolution of microscopic densities in phase space, we subsequently restrict to

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Dynamics of Annihilation I : Linearized Boltzmann Equation and Hydrodynamics

M. I. Garcia de Soria 1, P. Maynar 2, 3, G. Schehr 2, A. Barrat 2, E. Trizac 1 Physical Review E: Statistical, Nonlinear, and Soft Matter Physics 77 (2008) 051127 We study the non-equilibrium statistical mechanics of a system of freely moving particles, in which binary encounters lead either to an elastic collision or to the disappearance of the pair. Such a system of {\em

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