Coherent feedback-enhanced asymmetry of thermal process in open quantum systems: Cavity optomechanics

TL;DR

This paper explores how coherent feedback loops in cavity optomechanics can enhance entropy production and quantum correlations, pushing systems far from thermal equilibrium and improving thermal control of mechanical elements.

Contribution

It introduces a method to analyze entropy production in open quantum systems with coherent feedback, revealing the link between irreversibility and quantum correlations.

Findings

Entropy production rate is proportional to quantum mutual information in small-coupling limit.

Coherent feedback enhances entropy production during heating/cooling of the mechanical mirror.

Irreversibility and quantum correlations are interconnected and should be analyzed together.

Abstract

Entropy production is a fundamental concept in nonequilibrium thermodynamics, providing a direct measure of the irreversibility inherent in any physical process. In this work, we investigate in steady-state the enhancement of irreversibility employing coherent feedback loop. We evaluate the steady-state entropy production rate and quantum correlations by applying the quantum phase space formulation to calculate the entropy change. Our study reveals the essential contribution of coherent feedback in the thermal bath's input-noise operators, resulting in the system being driven far from thermal equilibrium. Our analysis shows that in the small-coupling limit, the entropy production rate is proportional to the quantum mutual information. We use for application the optomechanical system of Fabry-P\'erot cavity, and show that the picks of the entropy production corresponding of the heating/cooling of movable mirror are improved. Therefore, we conclude that irreversibility and quantum correlations are not independent and must be analyzed jointly. The results demonstrate the possibility of enhancement of entropy production and pave the way for promising quantum thermal applications through coherent feedback loop.