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Title: Loschmidt echo in one-dimensional interacting Bose gases

Abstract

We explore Loschmidt echo in two regimes of one-dimensional interacting Bose gases: the strongly interacting Tonks-Girardeau (TG) regime, and the weakly interacting mean-field regime. We find that the Loschmidt echo of a TG gas decays as a Gaussian when small (random and time independent) perturbations are added to the Hamiltonian. The exponent is proportional to the number of particles and the magnitude of a small perturbation squared. In the mean-field regime the Loschmidt echo shows richer behavior: it decays faster for larger nonlinearity, and the decay becomes more abrupt as the nonlinearity increases; it can be very sensitive to the particular realization of the noise potential, especially for relatively small nonlinearities.

Authors:
; ;  [1];  [2]
  1. Faculty of Electrical Engineering Mechanical Engineering and Naval Architecture, University of Split, Rudjera Boskovica BB, 21000 Split (Croatia)
  2. (Croatia)
Publication Date:
OSTI Identifier:
22095652
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. A; Journal Volume: 84; Journal Issue: 6; Other Information: (c) 2011 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; 74 ATOMIC AND MOLECULAR PHYSICS; BOSE-EINSTEIN GAS; DECAY; DISTURBANCES; HAMILTONIANS; MEAN-FIELD THEORY; NOISE; NONLINEAR PROBLEMS; ONE-DIMENSIONAL CALCULATIONS; POTENTIALS; RANDOMNESS

Citation Formats

Lelas, K., Seva, T., Buljan, H., and Department of Physics, University of Zagreb, Bijenicka c. 32, 10000 Zagreb. Loschmidt echo in one-dimensional interacting Bose gases. United States: N. p., 2011. Web. doi:10.1103/PHYSREVA.84.063601.
Lelas, K., Seva, T., Buljan, H., & Department of Physics, University of Zagreb, Bijenicka c. 32, 10000 Zagreb. Loschmidt echo in one-dimensional interacting Bose gases. United States. doi:10.1103/PHYSREVA.84.063601.
Lelas, K., Seva, T., Buljan, H., and Department of Physics, University of Zagreb, Bijenicka c. 32, 10000 Zagreb. 2011. "Loschmidt echo in one-dimensional interacting Bose gases". United States. doi:10.1103/PHYSREVA.84.063601.
@article{osti_22095652,
title = {Loschmidt echo in one-dimensional interacting Bose gases},
author = {Lelas, K. and Seva, T. and Buljan, H. and Department of Physics, University of Zagreb, Bijenicka c. 32, 10000 Zagreb},
abstractNote = {We explore Loschmidt echo in two regimes of one-dimensional interacting Bose gases: the strongly interacting Tonks-Girardeau (TG) regime, and the weakly interacting mean-field regime. We find that the Loschmidt echo of a TG gas decays as a Gaussian when small (random and time independent) perturbations are added to the Hamiltonian. The exponent is proportional to the number of particles and the magnitude of a small perturbation squared. In the mean-field regime the Loschmidt echo shows richer behavior: it decays faster for larger nonlinearity, and the decay becomes more abrupt as the nonlinearity increases; it can be very sensitive to the particular realization of the noise potential, especially for relatively small nonlinearities.},
doi = {10.1103/PHYSREVA.84.063601},
journal = {Physical Review. A},
number = 6,
volume = 84,
place = {United States},
year = 2011,
month =
}
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