Path Integral Formalism for Quantum Open Systems

Ruofan Chen

doi:10.1016/j.aop.2025.170083

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arXiv · 2506.08802

Path Integral Formalism for Quantum Open Systems

Ruofan Chen

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Abstract

This article provides a detailed derivation of the path integral formalism for both boson and fermion quantum open systems using coherent states. The formalism on the imaginary-time axis, Keldysh contour, and Kadanoff contour are given. The corresponding generating functional technique, which can be used to retrieve the environment information from the system correlation function, is also discussed.

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Ruofan Chen. 2025-06-10. Path Integral Formalism for Quantum Open Systems. https://doi.org/10.1016/j.aop.2025.170083

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