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arXiv:2507.23322 · Physical Review Research

Broken detailed balance and entropy production in completely positive and trace-preserving quantum Brownian motion

Anonymous, Gabriele Lo Monaco, Alberto Imparato, Mauro Paternostro, Sandro Donadi

Published Jul 17, 2026• 1 citation
arXivHTMLPDF

Abstract

We rigorously analyze the nonequilibrium thermodynamic behavior of various formulations of quantum Brownian motion using the framework of stochastic thermodynamics. While the widely used Caldeira-Leggett master equation exhibits desirable thermodynamic features—such as the fulfillment of a detailed balance—it fails to ensure complete positivity. In contrast, several completely positive and trace-preserving extensions turn out to be thermodynamically controversial. We show that such extensions introduce anomalous phase-space structures that violate detailed balance at the steady state, leading to nonvanishing entropy production and spurious nonequilibrium currents lacking a clear physical interpretation. Our results highlight a fundamental tension between quantum consistency and thermodynamic equilibration in open quantum systems.

DOI
10.1103/qqxn-qc4g

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