Quantum Dynamics, Master Equation and Equilibrium for a Qubit Coupled to a Thermal Boson Field

• URL: http://arxiv.org/abs/2510.13142v1
• Date: Wed, 15 Oct 2025 04:47:09 GMT
• Title: Quantum Dynamics, Master Equation and Equilibrium for a Qubit Coupled to a Thermal Boson Field
• Authors: Hiromichi Nakazato, Saverio Pascazio,
• Abstract summary: We analytically derive the exact -- though formal -- master equation for a two-level quantum system interacting with a bosonic environment.<n>The long-time behavior of the evolution operator governing the dynamics of both the system and the environment is analyzed.
• Score: 0.0
• License: http://creativecommons.org/licenses/by/4.0/
• Abstract: We analytically derive the exact -- though formal -- master equation for a two-level quantum system (qubit) interacting with a bosonic environment within the rotating-wave approximation, assuming the environment is initially in an arbitrary thermal state. The long-time behavior of the evolution operator governing the dynamics of both the system and the environment is analyzed, and the conditions under which the system approaches thermal equilibrium are examined.

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