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Stochastic wave function method for non-Markovian quantum master equations

H. P. Breuer·B. Kappler·F. Petruccione
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Abstract

A generalization of the stochastic wave function method to quantum master equations which are not in Lindblad form is developed. The proposed stochastic unravelling is based on a description of the reduced system in a doubled Hilbert space and it is shown, that this method is capable of simulating quantum master equations with negative transition rates. Non-Markovian effects in the reduced systems dynamics can be treated within this approach by employing the time-convolutionless projection operator technique. This ansatz yields a systematic perturbative expansion of the reduced systems dynamics in the coupling strength. Several examples such as the damped Jaynes Cummings model and the spontaneous decay of a two-level system into a photonic band gap are discussed. The power as well as the limitations of the method are demonstrated.

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H. P. Breuer, B. Kappler, F. Petruccione. 1999-06-07. Stochastic wave function method for non-Markovian quantum master equations. https://doi.org/10.1103/physreva.59.1633

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