Transient dynamics of the Anderson impurity model out of equilibrium

TL;DR

This paper investigates the transient behavior of the Anderson impurity model out of equilibrium, revealing how finite bandwidths influence time-dependent current-voltage characteristics and level populations.

Contribution

It extends analytical and numerical methods to study transient dynamics in the Anderson impurity model, including noninteracting and interacting cases with finite bandwidth effects.

Findings

Transient dynamics depend on electrode bandwidth.

Transient current-voltage characteristics differ from steady state.

Analytical solutions for noninteracting case extended to interacting case.

Abstract

We discuss the transient effects in the Anderson impurity model that occur when two fermionic continua with finite bandwidths are instantaneously coupled to a central level. We present results for the analytically solvable noninteracting resonant level system first and then consistently extend them to the interacting case using the conventional perturbation theory and recently developed nonequilibrium Monte Carlo simulation schemes. The main goal is to gain an understanding of the full time-dependent nonlinear current-voltage characteristics and the population probability of the central level. We find that, contrary to the steady state, the transient dynamics of the system depends sensitively on the bandwidth of the electrode material.