Quantum caloric effects

TL;DR

This paper develops a quantum Maxwell relationship to better understand caloric effects in quantum systems, revealing links between entropy changes and quantum correlations, with implications for quantum caloric devices.

Contribution

It derives general expressions for quantum caloric potentials using a quantum Maxwell relationship, connecting quantum correlations to caloric effects.

Findings

Recover classical caloric behavior as a special case.

Show that isothermal entropy change relates to quantum correlations.

Provide a framework for analyzing quantum caloric effects.

Abstract

Quantum thermodynamics aims to explore quantum features to enhance energy conversion beyond classical limits. While significant progress has been made, the understanding of caloric potentials in quantum systems remains incomplete. In this context, this study focuses on deriving general expressions for these caloric potentials, by developing a quantum Maxwell relationship obtained from a thermal average form of the Ehrenfest theorem. Our results recover the classical cases and also reveal that the isothermal entropy change can be related to genuine quantum correlations in the system. Thus, this work aims to contribute to the understanding of the caloric behavior of quantum systems and their potential implication in caloric devices.