Quantum processes as thermodynamic resources: the role of non-Markovianity

TL;DR

This paper investigates how non-Markovian quantum processes can serve as valuable thermodynamic resources, enhancing work extraction capabilities through memory effects and correlations.

Contribution

It establishes a general operational link between non-Markovianity and increased work extraction in quantum thermodynamics using process tensors.

Findings

Non-Markovianity enhances work distillation from quantum processes.

Three physical mechanisms enable increased work extraction due to non-Markovian effects.

A quantifier of non-Markovianity directly relates to the work extractable from quantum processes.

Abstract

Quantum thermodynamics studies how quantum systems and operations may be exploited as sources of work to perform useful thermodynamic tasks. In real-world conditions, the evolution of open quantum systems typically displays memory effects, resulting in a non-Markovian dynamics. The associated information backflow has been observed to provide advantage in certain thermodynamic tasks. However, a general operational connection between non-Markovianity and thermodynamics in the quantum regime has remained elusive. Here, we analyze the role of non-Markovianity in the central task of extracting work via thermal operations from general multitime quantum processes, as described by process tensors. By defining a hierarchy of four classes of extraction protocols, expressed as quantum combs, we reveal three different physical mechanisms (work investment, multitime correlations, and system-environment correlations) through which non-Markovianity increases the work distillable from the process. The advantages arising from these mechanisms are linked precisely to a quantifier of the non-Markovianity of the process. These results show in very general terms how non-Markovianity of any given quantum process is a fundamental resource that unlocks an enhanced performance in thermodynamics.