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Title: Bogoliubov theory for mutually coherent hybrid atomic molecular condensates: Quasiparticles and superchemistry

Abstract

We investigate the equilibrium properties of a hybrid atomic and molecular Bose-Einstein condensate in the context of the Feshbach-resonant quantum many-body model. We analyze fully the mean-field solutions of the system for a general choice of interaction parameters. The quantum fluctuations of the system are obtained from the Bogoliubov theory that characterizes the quasiparticle excitations of the system. In particular we find that the excitation energies have two branches: a Goldstone mode and a second one containing a gap. Both gap energy and phonon velocities are functions of the composition, and our analysis indicates that for a large range of parameter space the system is unstable near a Feshbach resonance.

Authors:
;  [1]; ; ;  [2]
  1. Department of Physics, National Dong Hwa University, Shoufeng, 974 Hua-Lien, Taiwan (China)
  2. Instituto de Fisica, Universidade de Sao Paulo, CP 66318 CEP 05389-970, Sao Paulo, SP (Brazil)
Publication Date:
OSTI Identifier:
20786757
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. A; Journal Volume: 73; Journal Issue: 1; Other Information: DOI: 10.1103/PhysRevA.73.013615; (c) 2006 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
74 ATOMIC AND MOLECULAR PHYSICS; BOSE-EINSTEIN CONDENSATION; EQUILIBRIUM; EXCITATION; FLUCTUATIONS; MANY-BODY PROBLEM; MATHEMATICAL SOLUTIONS; MEAN-FIELD THEORY; PHONONS; RADIATION PRESSURE; RESONANCE

Citation Formats

Lin, C.-Y., Lee, D.-S., Passos, E. J. V. de, Toledo Piza, A. F. R. de, and Hussein, M. S. Bogoliubov theory for mutually coherent hybrid atomic molecular condensates: Quasiparticles and superchemistry. United States: N. p., 2006. Web. doi:10.1103/PHYSREVA.73.0.
Lin, C.-Y., Lee, D.-S., Passos, E. J. V. de, Toledo Piza, A. F. R. de, & Hussein, M. S. Bogoliubov theory for mutually coherent hybrid atomic molecular condensates: Quasiparticles and superchemistry. United States. doi:10.1103/PHYSREVA.73.0.
Lin, C.-Y., Lee, D.-S., Passos, E. J. V. de, Toledo Piza, A. F. R. de, and Hussein, M. S. Sun . "Bogoliubov theory for mutually coherent hybrid atomic molecular condensates: Quasiparticles and superchemistry". United States. doi:10.1103/PHYSREVA.73.0.
@article{osti_20786757,
title = {Bogoliubov theory for mutually coherent hybrid atomic molecular condensates: Quasiparticles and superchemistry},
author = {Lin, C.-Y. and Lee, D.-S. and Passos, E. J. V. de and Toledo Piza, A. F. R. de and Hussein, M. S.},
abstractNote = {We investigate the equilibrium properties of a hybrid atomic and molecular Bose-Einstein condensate in the context of the Feshbach-resonant quantum many-body model. We analyze fully the mean-field solutions of the system for a general choice of interaction parameters. The quantum fluctuations of the system are obtained from the Bogoliubov theory that characterizes the quasiparticle excitations of the system. In particular we find that the excitation energies have two branches: a Goldstone mode and a second one containing a gap. Both gap energy and phonon velocities are functions of the composition, and our analysis indicates that for a large range of parameter space the system is unstable near a Feshbach resonance.},
doi = {10.1103/PHYSREVA.73.0},
journal = {Physical Review. A},
number = 1,
volume = 73,
place = {United States},
year = {Sun Jan 15 00:00:00 EST 2006},
month = {Sun Jan 15 00:00:00 EST 2006}
}
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