Europhys. Lett.
Volume 72, Number 3, November 2005
Page(s) 334 - 340
Section General
Published online 05 October 2005
Europhys. Lett., 72 (3), pp. 334-340 (2005)
DOI: 10.1209/epl/i2005-10262-4

Stochastic simulation of quantum dissipative dynamics

Y. Zhou, Y. Yan and J. Shao

State Key Laboratory of Molecular Reaction Dynamics, Institute of Chemistry Chinese Academy of Sciences - Beijing 100080, PRC

received 3 August 2005; accepted in final form 14 September 2005
published online 5 October 2005

As a system can be separated from its heat bath via a decoupling scheme based on the Hubbard-Stratonovich transformation, the quantum dissipative dynamics is exactly described by the average of the random system moving in the stochastic field induced by the bath. As a test of this stochastic formalism, a direct numerical implementation is employed to simulate the spontaneous decay of a two-state atom. In contrast, the validity of a deterministic algorithm based on the stochastic scheme is investigated. Moreover, a mixed random-deterministic approach is established and its efficiency is exemplified by studying the exact dynamics for the spin-boson model at zero temperature.

03.65.Yz - Decoherence; open systems; quantum statistical methods.
05.30.-d - Quantum statistical mechanics.
05.10.Gg - Stochastic analysis methods (Fokker-Planck, Langevin, etc.).

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