Real-time path integral approach to nonequilibrium many-body quantum system

TL;DR

This paper introduces a real-time path integral Monte Carlo method to analyze the dynamics of many-body quantum systems until they reach a nonequilibrium stationary state, effectively handling various physical regimes.

Contribution

It develops an augmented exact reduced equation combined with path integral Monte Carlo for studying nonequilibrium quantum dynamics.

Findings

Applicable across a wide temperature range

Effective for both weak and strong electron-phonon couplings

Demonstrated on inelastic tunneling spectroscopy model

Abstract

A real-time path integral Monte Carlo approach is developed to study the dynamics in a many-body quantum system until reaching a nonequilibrium stationary state. The approach is based on augmenting an exact reduced equation for the evolution of the system in the interaction picture which is amenable to an efficient path integral (worldline) Monte Carlo approach. Results obtained for a model of inelastic tunneling spectroscopy reveal the applicability of the approach to a wide range of physically important regimes, including high (classical) and low (quantum) temperatures, and weak (perturbative) and strong electron-phonon couplings.