Transition to instability in a periodically kicked BoseEinstein condensate on a ring
Abstract
A periodically kicked ring of a BoseEinstein condensate is considered as a nonlinear generalization of the quantum kicked rotor, where the nonlinearity stems from the meanfield interactions between the condensed atoms. For weak interactions, periodic motion (antiresonance) becomes quasiperiodic (quantum beating) but remains stable. There exists a critical strength of interactions beyond which quasiperiodic motion becomes chaotic, resulting in an instability of the condensate manifested by exponential growth in the number of noncondensed atoms. In the stable regime, the system remains predominantly in the two lowest energy states and may be mapped onto a spin model, from which we obtain an analytic expression for the beat frequency and discuss the route to instability. We numerically explore a parameter regime for the occurrence of instability and reveal the characteristic density profile for both condensed and noncondensed atoms. The Arnold diffusion to higher energy levels is found to be responsible for the transition to instability. Similar behavior is observed for dynamically localized states (essentially quasiperiodic motions), where stability remains for weak interactions but is destroyed by strong interactions.
 Authors:
 Institute of Applied Physics and Computational Mathematics, Beijing 100088 (China)
 (United States)
 Department of Physics, University of Texas, Austin, Texas 787121081 (United States)
 Publication Date:
 OSTI Identifier:
 20786743
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Physical Review. A; Journal Volume: 73; Journal Issue: 1; Other Information: DOI: 10.1103/PhysRevA.73.013601; (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; ATOMS; BOSEEINSTEIN CONDENSATION; CHAOS THEORY; DIFFUSION; ENERGY LEVELS; INSTABILITY; MEANFIELD THEORY; NONLINEAR PROBLEMS; PERIODICITY; SPIN; STRONG INTERACTIONS; WEAK INTERACTIONS
Citation Formats
Liu Jie, Department of Physics, University of Texas, Austin, Texas 787121081, Zhang Chuanwei, Raizen, Mark G., Center for Nonlinear Dynamics, University of Texas, Austin, Texas 787121081, and Niu Qian. Transition to instability in a periodically kicked BoseEinstein condensate on a ring. United States: N. p., 2006.
Web. doi:10.1103/PHYSREVA.73.0.
Liu Jie, Department of Physics, University of Texas, Austin, Texas 787121081, Zhang Chuanwei, Raizen, Mark G., Center for Nonlinear Dynamics, University of Texas, Austin, Texas 787121081, & Niu Qian. Transition to instability in a periodically kicked BoseEinstein condensate on a ring. United States. doi:10.1103/PHYSREVA.73.0.
Liu Jie, Department of Physics, University of Texas, Austin, Texas 787121081, Zhang Chuanwei, Raizen, Mark G., Center for Nonlinear Dynamics, University of Texas, Austin, Texas 787121081, and Niu Qian. Sun .
"Transition to instability in a periodically kicked BoseEinstein condensate on a ring". United States.
doi:10.1103/PHYSREVA.73.0.
@article{osti_20786743,
title = {Transition to instability in a periodically kicked BoseEinstein condensate on a ring},
author = {Liu Jie and Department of Physics, University of Texas, Austin, Texas 787121081 and Zhang Chuanwei and Raizen, Mark G. and Center for Nonlinear Dynamics, University of Texas, Austin, Texas 787121081 and Niu Qian},
abstractNote = {A periodically kicked ring of a BoseEinstein condensate is considered as a nonlinear generalization of the quantum kicked rotor, where the nonlinearity stems from the meanfield interactions between the condensed atoms. For weak interactions, periodic motion (antiresonance) becomes quasiperiodic (quantum beating) but remains stable. There exists a critical strength of interactions beyond which quasiperiodic motion becomes chaotic, resulting in an instability of the condensate manifested by exponential growth in the number of noncondensed atoms. In the stable regime, the system remains predominantly in the two lowest energy states and may be mapped onto a spin model, from which we obtain an analytic expression for the beat frequency and discuss the route to instability. We numerically explore a parameter regime for the occurrence of instability and reveal the characteristic density profile for both condensed and noncondensed atoms. The Arnold diffusion to higher energy levels is found to be responsible for the transition to instability. Similar behavior is observed for dynamically localized states (essentially quasiperiodic motions), where stability remains for weak interactions but is destroyed by strong interactions.},
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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