Non-equilibrium Green's functions and their relation to the negative differential conductance in the interacting resonant level model
Abstract
We evaluate the non-equilibrium single particle Green's functions in the steady state of the interacting resonant level model (IRLM) under the effect of an applied bias voltage. Employing the so-called auxiliary master equation approach, we present accurate nonperturbative results for the non-equilibrium spectral and effective distribution functions, as well as for the current-voltage characteristics. We find a drastic change of these spectral properties between the regimes of low and high bias voltages and discuss the relation of these changes to the negative differential conductance (NDC), a prominent feature in the non-equilibrium IRLM. The anomalous evolution of the distribution function next to the impurity shown by our calculations suggests a mechanism whereby the impurity gets effectively decoupled from the leads at voltages where the NDC sets in, in agreement with previous renormalization group approaches. This scenario is qualitatively confirmed by a Hartree-Fock treatment of the model.
Keywords
Cite
@article{arxiv.1812.08618,
title = {Non-equilibrium Green's functions and their relation to the negative differential conductance in the interacting resonant level model},
author = {Max E. Sorantin and Wolfgang von der Linden and Roman Lucrezi and Enrico Arrigoni},
journal= {arXiv preprint arXiv:1812.08618},
year = {2019}
}