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

• URL: http://arxiv.org/abs/2310.11729v1
• Date: Wed, 18 Oct 2023 05:59:15 GMT
• Title: Diagrammatic representation and nonperturbative approximation of exact time-convolutionless master equation
• Authors: Bing Gu
• Abstract summary: We provide a general framework to model non-Markovian dynamics of an open quantum system with a time-local generator. A truncation of the perturbation expansion leads to the perturbative time-convolutionless quantum master equations.
• Score: 0.0
• License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
• 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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