Effective temperature of a dissipative driven mesoscopic system

TL;DR

This paper investigates the nonequilibrium behavior of a driven mesoscopic metallic ring, showing that an effective temperature can describe fluctuation-dissipation deviations in weakly coupled systems.

Contribution

It introduces a framework linking Green functions to an effective temperature in a driven mesoscopic system under weak environmental coupling.

Findings

Effective temperature describes fluctuation-dissipation deviations.

Linear response regime with weak heat transfer allows for this effective temperature.

Analysis can be extended to other nonequilibrium mesoscopic systems.

Abstract

We study the nonequilibrium dynamics of a mesoscopic metallic ring threaded by a time-dependent magnetic field and coupled to an electronic reservoir. We analyze the relation between the (non-stationary) real-time Keldysh and retarded Green functions and we find that, in the linear response regime with weak heat transfer to the environment, an effective temperature accounts for the modification of the equilibrium fluctuation-dissipation relation. We discuss possible extensions of this analysis.