Please use this identifier to cite or link to this item: https://doi.org/10.1103/PhysRevE.66.056208
Title: Crossover of quantum Loschmidt echo from golden-rule decay to perturbation-independent decay
Authors: Wang, W.-G. 
Li, B. 
Issue Date: Nov-2002
Citation: Wang, W.-G., Li, B. (2002-11). Crossover of quantum Loschmidt echo from golden-rule decay to perturbation-independent decay. Physical Review E - Statistical, Nonlinear, and Soft Matter Physics 66 (5) : 056208/1-056208/9. ScholarBank@NUS Repository. https://doi.org/10.1103/PhysRevE.66.056208
Abstract: We study the crossover of the quantum Loschmidt echo (or fidelity) from the golden-rule regime to the perturbation-independent exponential decay regime by using the kicked top model. It is shown that the deviation of the perturbation-independent decay of the averaged fidelity from the Lyapunov decay results from quantum fluctuations in individual fidelity, which are caused by the coherence in the initial coherent states. With an averaging procedure suppressing the quantum fluctuations effectively, the perturbation-independent decay is found to be close to the Lyapunov decay. We also show that the Fourier transform of the fidelity is determined directly by the initial state and the eigenstates of the Floquet operators of the two classically chaotic systems concerned. The absolute value part and the phase part of the Fourier transform of the fidelity are found to be divided into several correlated parts, which is a manifestation of the coherence of the initial coherent state. In the whole crossover region, some important properties of the fidelity, such as the exponent of its exponential decay and the short initial time within which the fidelity almost does not change, are found to be closely related to the properties of the central part of its Fourier transform. © 2002 The American Physical Society.
Source Title: Physical Review E - Statistical, Nonlinear, and Soft Matter Physics
URI: http://scholarbank.nus.edu.sg/handle/10635/96130
ISSN: 15393755
DOI: 10.1103/PhysRevE.66.056208
Appears in Collections:Staff Publications

Show full item record
Files in This Item:
There are no files associated with this item.

Google ScholarTM

Check

Altmetric


Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.