Thermodynamics of weakly measured quantum systems

TL;DR

This paper extends stochastic thermodynamics to quantum systems under continuous measurement, defining work and heat at the quantum trajectory level, and demonstrates these concepts with a driven two-level system.

Contribution

It introduces quantum definitions of work and heat for monitored systems, extending thermodynamic laws to quantum trajectories, and employs feedback control to analyze work statistics.

Findings

Distinguished quantum work from heat in monitored systems

Extended first and second laws to quantum stochastic thermodynamics

Used feedback control to analyze work statistics in quantum systems

Abstract

We consider continuously monitored quantum systems and introduce definitions of work and heat along individual quantum trajectories that are valid for coherent superpositions of energy eigenstates. We use these quantities to extend the first and second laws of stochastic thermodynamics to the quantum domain. We illustrate our results with the case of a weakly measured driven two-level system and show how to distinguish between quantum work and heat contributions. We finally employ quantum feedback control to suppress detector backaction and determine the work statistics.