The Crooks relation in optical spectra - universality in work distributions for weak local quenches

TL;DR

This paper demonstrates that optical spectra can reveal universal work distribution relations in quantum systems undergoing weak local quenches, linking spectral measurements to non-equilibrium fluctuation theorems.

Contribution

It establishes a universal Crooks relation in optical spectra for weak local perturbations, connecting spectral data to work distributions in quantum quenches.

Findings

Universal Crooks relation in absorption and emission spectra.

Spectral measurements encode work distribution functions.

Application to X-ray edge problem and Kondo exciton.

Abstract

We show that work distributions and non-equilibrium work fluctuation theorems can be measured in optical spectra for a wide class of quantum systems. We consider systems where the absorption or emission of a photon corresponds to the sudden switch on or off of a local perturbation. For the particular case of a weak local perturbation, the Crooks relation establishes a universal relation in absorption as well as in emission spectra. Due to a direct relation between the spectra and work distribution functions this is equivalent to universal relations in work distributions for weak local quenches. As two concrete examples we treat the X-ray edge problem and the Kondo exciton.