Energetics of Fano coherence generation

TL;DR

This paper investigates the quantum and thermodynamic properties of Fano coherences in a three-level system, demonstrating their role in work extraction and analyzing their efficiency in nonequilibrium conditions.

Contribution

It introduces a method to certify quantum traits of Fano coherences via quasiprobability distributions and explores their thermodynamic implications for work extraction.

Findings

Fano coherences can be linked to non-positive quasiprobability distributions.

Generation of Fano coherences can enable work extraction in nonequilibrium regimes.

The thermodynamic efficiency of coherence-driven work processes is analyzed.

Abstract

In a multi-level quantum system Fano coherences stand for the formation of quantum coherences due to the interaction with the continuum of modes characterizing an incoherent process. When the incoherent source vanishes, Fano coherences tend to disappear. In this paper we propose a V-type three-level quantum system on which we certify the presence of genuinely quantum traits underlying the generation of Fano coherences. We do this by determining work conditions that allows for the loss of positivity of the Kirkwood-Dirac quasiprobability distribution of the stochastic energy variations within the discrete system. We also show the existence of nonequilibrium regimes where the generation of Fano coherences leads to a non-negligible amount of extractable work, however provided the initial state of the discrete system is in a superposition of the energy eigenbasis. We conclude the paper by studying the thermodynamic efficiency of the whole process.