Decoherence, entanglement, and chaos in the Dicke model

Journal Article · Thu Apr 01 04:00:00 EST 2004 · Physical Review. A

DOI:https://doi.org/10.1103/PhysRevA.69.042110· OSTI ID:20640945

Xiwen, Hou ^[1]; Bambi, Hu ^[1]

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1. Department of Physics and Centre for Nonlinear Studies, Hong Kong Baptist University, Hong Kong (China)

The dynamical properties of quantum entanglement in the Dicke model without rotating-wave approximation are investigated in terms of the reduced-density linear entropy. The characteristic time of decoherence process in the early-time evolution is numerically obtained and it is shown that the characteristic time decreases as the coupling parameter increases. The mean entanglement, which is defined to be averaged over time, is employed to describe the influences of both quantum phase transition and corresponding classical chaos on the behavior of entanglement. For a given energy, initial conditions are taken to be minimum uncertainty wave packets centered at regular and chaotic regions of the classical phase space. It is shown that the entanglement has a distinct change at the quantum phase transition, and that the entanglement for regular initial conditions is smaller than that for chaotic ones in the case of weak coupling, while it fluctuates with small amplitude in strong coupling and for chaotic initial conditions.

• OSTI ID: 20640945
• Journal Information: Physical Review. A, Journal Name: Physical Review. A Journal Issue: 4 Vol. 69; ISSN 1050-2947; ISSN PLRAAN
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
74 ATOMIC AND MOLECULAR PHYSICS
AMPLITUDES
CHAOS THEORY
CORRELATIONS
COUPLING
DENSITY
ENERGY LEVELS
ENTROPY
EVOLUTION
FLUCTUATIONS
PHASE SPACE
PHASE TRANSFORMATIONS
QUANTUM MECHANICS
WAVE PACKETS