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arXiv · 2310.11729

Diagrammatic representation and nonperturbative approximation of exact time-convolutionless master equation

Bing Gu
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Abstract

The time-convolutionless master equation provides a general framework to model non-Markovian dynamics of an open quantum system with a time-local generator. A diagrammatic representation is developed and proven for the perturbative expansion of the exact time-local generator for an open quantum system interacting with arbitrary environments. A truncation of the perturbation expansion leads to the perturbative time-convolutionless quantum master equations. We further introduce a nonperturbative approach that approximates the time-convolutionless generator as a nested time-ordered exponential function.

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Bing Gu. 2023-10-18. Diagrammatic representation and nonperturbative approximation of exact time-convolutionless master equation. https://arxiv.org/abs/2310.11729

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