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The non-Markovian quantum behavior of open systems: An exact Monte Carlo method employing stochastic product states

Heinz-Peter Breuer
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Abstract

It is shown that the exact dynamics of a composite quantum system can be represented through a pair of product states which evolve according to a Markovian random jump process. This representation is used to design a general Monte Carlo wave function method that enables the stochastic treatment of the full non-Markovian behavior of open quantum systems. Numerical simulations are carried out which demonstrate that the method is applicable to open systems strongly coupled to a bosonic reservoir, as well as to the interaction with a spin bath. Full details of the simulation algorithms are given, together with an investigation of the dynamics of fluctuations. Several potential generalizations of the method are outlined.

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Heinz-Peter Breuer. 2003-09-15. The non-Markovian quantum behavior of open systems: An exact Monte Carlo method employing stochastic product states. https://doi.org/10.1140/epjd%2Fe2004-00010-x

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