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arXiv · 1701.06534

On generalized semi-Markov quantum evolution

Dariusz Chruściński·Andrzej Kossakowski
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Abstract

We provide a large class of quantum evolution governed by the memory kernel master equation. This class defines quantum analog of so called semi-Markov classical stochastic evolution. In this Letter for the first time we provide a proper definition of quantum semi-Markov evolution and using the appropriate gauge freedom we propose a suitable generalization which contains majority of examples considered so far in the literature. The key concepts are quantum counterparts of classical waiting time distribution and survival probability -- quantum waiting time operator and quantum survival operator, respectively. In particular collision models and its generalizations considered recently are special examples of generalized semi-Markov evolution. This approach allows for an interesting generalization of trajectory description of the quantum dynamics in terms of POVM densities.

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Dariusz Chruściński, Andrzej Kossakowski. 2017-01-23. On generalized semi-Markov quantum evolution. https://doi.org/10.1103/physreva.95.042131

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