The characteristic functions of quantum heat with baths at different temperatures

TL;DR

This paper develops a framework for analyzing quantum heat in systems coupled to multiple baths at different temperatures, extending previous single-bath results and enabling the study of heat flow and correlations.

Contribution

It introduces a characteristic function approach for quantum heat with multiple baths, bridging quantum and classical thermodynamics and extending earlier single-bath results.

Findings

Characteristic function formalism for quantum heat with multiple baths

Extension of previous single-bath quantum heat results

Potential to study heat flow and correlations in quantum systems

Abstract

This paper is about quantum heat defined as the change in energy of a bath during a process. The presentation takes into account recent developments in classical strong-coupling thermodynamics, and addresses a version of quantum heat which satisfies quantum-classical correspondence. The characteristic function and the full counting statistics of quantum heat are shown to be formally similar. The paper further shows that the method can be extended to more than one bath, e.g. two baths at different temperatures, which opens up the prospect of studying correlations and heat flow. The paper extends earlier results on the expected quantum heat in the setting of one bath (Aurell \& Eichhorn 2015, Aurell 2017).