Nonequilibrium Fluctuation-Dissipation Theorems for Interacting Quantum Transport

TL;DR

This paper derives non-equilibrium fluctuation-dissipation relations for interacting quantum transport systems, analyzing their dependence on interactions and non-equilibrium conditions, with implications for nanoscale transport experiments.

Contribution

The paper introduces NE fluctuation-dissipation relations for both one- and two-particle correlations in interacting quantum transport, supported by self-consistent Green's function calculations.

Findings

FD relations for one-particle correlations depend strongly on NE conditions and interactions

FD relations for two-particle correlations are less affected by interactions

Two-particle correlations can reveal chemical potential and temperature gradients

Abstract

We study non-equilibrium (NE) fluctuation-dissipation (FD) relations in the context of quantum thermoelectric transport through a two-terminal nanodevice, in the steady-state and with interaction. The FD relations for the one- and two-particle correlation functions are derived. Numerical applications, using self-consistent NE Green's functions calculations, are given for electron-phonon interaction in the central region. We find that the FD relations for the one-particle correlation function are strongly dependent on both the NE conditions and the interactions, while they are much less dependent on the interactions for the two-particle correlation. This suggests interesting applications for single-molecule and other nanoscale transport experiments: the two-particle correlation functions, obtained from noise and transport measurement, provide information about the gradients of chemical potential and temperature, and other properties of the system.