Heat flux and information backflow in cold condensed matter systems

TL;DR

This paper investigates non-Markovian effects in a quantum spin-boson system with a cold reservoir, revealing that information backflow does not always align with heat backflow and exploring how temperature, coupling, and driving influence these effects.

Contribution

It provides an exact analysis of information and heat exchange in a cold reservoir spin-boson model, highlighting the nuanced relationship between information backflow and heat flow.

Findings

Information backflow does not necessarily coincide with heat backflow.

Temperature and coupling strength significantly affect information exchange.

Driving can modify the backflow of information, enabling reservoir engineering.

Abstract

We examine non-Markovian effects in an open quantum system from the point of view of information flow. To this end, we consider the spin-boson model with a cold reservoir, accounting for the exact time-dependent correlations between the system and the bath to study the exchange of information and heat. We use an information theoretic measure of the relevant memory effects and demonstrate that the information backflow from the reservoir to the system does not necessarily correlate with the backflow of heat. We also examine the influence of temperature and coupling strength on the loss and gain of information between the system and the bath. Finally, we discuss how additional driving changes the backflow of information, giving rise to potential applications in reservoir engineering.