Correlations as a resource in quantum thermodynamics

TL;DR

This paper investigates how correlations can serve as a resource in quantum thermodynamics, reducing energy costs in state formation, especially in the single-shot regime, and connecting to free energy in the asymptotic limit.

Contribution

It introduces a framework for understanding correlations as a thermodynamic resource, quantifies their impact on energetic costs, and extends results to the asymptotic limit.

Findings

Correlations reduce the energetic cost of creating multiple copies of a quantum state.

Minimum cost for state formation can be achieved by allowing correlations.

In the asymptotic limit, correlations relate to free energy as a resource.

Abstract

The presence of correlations in physical systems can be a valuable resource for many quantum information tasks. They are also relevant in thermodynamic transformations, and their creation is usually associated to some energetic cost. In this work, we study the role of correlations in the thermodynamic process of state formation in the single-shot regime, and find that correlations can also be viewed as a resource. First, we show that the energetic cost of creating multiple copies of a given state can be reduced by allowing correlations in the final state. We obtain the minimum cost for every finite number of subsystems, and then we show that this feature is not restricted to the case of copies. More generally, we demonstrate that in the asymptotic limit, by allowing a logarithmic amount of correlations, we can recover standard results where the free energy quantifies this minimum cost.