Impurity model for non-equilibrium steady states

TL;DR

This paper introduces a non-equilibrium impurity model for the Hubbard model under electric fields, using a quantum Monte Carlo method to obtain steady-state solutions, advancing the understanding of non-equilibrium many-body systems.

Contribution

It presents a novel impurity model for non-equilibrium steady states and a non-perturbative quantum Monte Carlo approach to solve it, applicable to driven lattice systems.

Findings

Validates the impurity model for non-equilibrium conditions

Demonstrates the effectiveness of the quantum Monte Carlo solver

Provides insights into steady-state properties of driven Hubbard models

Abstract

We propose an out-of-equilibrium impurity model for the dynamical mean-field description of the Hubbard model driven by a finite electric field. The out-of-equilibrium impurity environment is represented by a collection of equilibrium reservoirs at different chemical potentials. We discuss the validity of the impurity model and propose a non-perturbative method, based on a quantum Monte Carlo solver, which provides the steady-state solutions of the impurity and original lattice problems. We discuss the relevance of this approach to other non-equilibrium steady-state contexts.