Thermodynamics of quantum Brownian motion with internal degrees of freedom: the role of entanglement in the strong-coupling quantum regime

TL;DR

This paper investigates how entanglement affects the thermodynamics of quantum Brownian motion, especially in strong coupling regimes, by analyzing models of coupled oscillators and their heat-entropy relations.

Contribution

It introduces a model of two coupled Brownian oscillators to explore entanglement's role in quantum thermodynamics, extending previous single-particle analyses.

Findings

Entanglement influences heat and entropy exchange in quantum systems.

Internal coupling modifies thermodynamic behavior compared to single-particle models.

Results provide insights into the violation of classical thermodynamic inequalities in quantum regimes.

Abstract

We study the influence of entanglement on the relation between the statistical entropy of an open quantum system and the heat exchanged with a low temperature environment. A model of quantum Brownian motion of the Caldeira-Leggett type - for which a violation of the Clausius inequality has been stated by Th.M. Nieuwenhuizen and A.E. Allahverdyan [Phys. Rev. E 66, 036102 (2002)] - is reexamined and the results of the cited work are put into perspective. In order to address the problem from an information theoretical viewpoint a model of two coupled Brownian oscillators is formulated that can also be viewed as a continuum version of a two-qubit system. The influence of an additional internal coupling parameter on heat and entropy changes is described and the findings are compared to the case of a single Brownian particle.