Nonequilibrium Fock space for the electron transport problem

TL;DR

This paper introduces a nonequilibrium Fock space framework based on thermo field dynamics, enabling the study of steady-state electron transport in interacting quantum systems with compatibility to advanced electronic structure methods.

Contribution

It develops a novel nonequilibrium Fock space formalism and demonstrates its application to electron transport, integrating with existing electronic structure techniques.

Findings

Successful formulation of nonequilibrium quasiparticles

Application to electron transport in interacting regions

Compatibility with coupled cluster and configuration interaction methods

Abstract

Based on the formalism of thermo field dynamics we propose a concept of nonequilibrium Fock space and nonequilibrium quasiparticles for quantum many-body system in nonequilibrium steady state. We develop a general theory as well as demonstrate the utility of the approach on the example of electron transport through the interacting region. The proposed approach is compatible with advanced methods of electronic structure calculations such as coupled cluster theory and configuration interaction.