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Title: Periodic modulation effect on self-trapping of two weakly coupled Bose-Einstein condensates

Abstract

With phase space analysis approach, we investigate the self-trapping phenomenon for two weakly coupled Bose-Einstein condensates (BECs) in a symmetric double well potential. We identify two kinds of self-trapping by their different relative phase behavior. By applying a periodic modulation on the energy bias of the system we find that the self-trapping can be controlled, in other words, the transition parameters can be adjusted effectively by the periodic modulation. Analytic expressions for the dependence of the transition parameters on the modulation parameters are derived for high- and low-frequency modulations. For an intermediate-frequency modulation, we find the resonance between the periodic modulation and nonlinear Rabi oscillation dramatically affect the tunneling dynamics and demonstrate many phenomena. Finally, we study the effects of many-body quantum fluctuation on the self-trapping and discuss the possible experimental realization.

Authors:
 [1];  [2]; ;  [1]
  1. Institute of Applied Physics and Computational Mathematics, P.O. Box 8009 (28), 100088 Beijing (China)
  2. (China)
Publication Date:
OSTI Identifier:
20786761
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. A; Journal Volume: 73; Journal Issue: 1; Other Information: DOI: 10.1103/PhysRevA.73.013619; (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; FLUCTUATIONS; FREQUENCY MODULATION; MANY-BODY PROBLEM; NONLINEAR PROBLEMS; OPTICS; OSCILLATIONS; PERIODICITY; PHASE SPACE; POTENTIALS; RESONANCE; TRAPPING; TUNNEL EFFECT

Citation Formats

Wang Guanfang, Institute of Physical Science and Technology, Lanzhou University, 730000 Lanzhou, Fu Libin, and Liu Jie. Periodic modulation effect on self-trapping of two weakly coupled Bose-Einstein condensates. United States: N. p., 2006. Web. doi:10.1103/PHYSREVA.73.0.
Wang Guanfang, Institute of Physical Science and Technology, Lanzhou University, 730000 Lanzhou, Fu Libin, & Liu Jie. Periodic modulation effect on self-trapping of two weakly coupled Bose-Einstein condensates. United States. doi:10.1103/PHYSREVA.73.0.
Wang Guanfang, Institute of Physical Science and Technology, Lanzhou University, 730000 Lanzhou, Fu Libin, and Liu Jie. Sun . "Periodic modulation effect on self-trapping of two weakly coupled Bose-Einstein condensates". United States. doi:10.1103/PHYSREVA.73.0.
@article{osti_20786761,
title = {Periodic modulation effect on self-trapping of two weakly coupled Bose-Einstein condensates},
author = {Wang Guanfang and Institute of Physical Science and Technology, Lanzhou University, 730000 Lanzhou and Fu Libin and Liu Jie},
abstractNote = {With phase space analysis approach, we investigate the self-trapping phenomenon for two weakly coupled Bose-Einstein condensates (BECs) in a symmetric double well potential. We identify two kinds of self-trapping by their different relative phase behavior. By applying a periodic modulation on the energy bias of the system we find that the self-trapping can be controlled, in other words, the transition parameters can be adjusted effectively by the periodic modulation. Analytic expressions for the dependence of the transition parameters on the modulation parameters are derived for high- and low-frequency modulations. For an intermediate-frequency modulation, we find the resonance between the periodic modulation and nonlinear Rabi oscillation dramatically affect the tunneling dynamics and demonstrate many phenomena. Finally, we study the effects of many-body quantum fluctuation on the self-trapping and discuss the possible experimental realization.},
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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