One-Dimensional Quantum Transport Affected by a Background Medium: Fluctuations versus Correlations

TL;DR

This paper investigates how background medium fluctuations and correlations influence quantum transport in a one-dimensional fermion-boson system, revealing their impact on spectral properties and phase transitions.

Contribution

It introduces a comprehensive analysis of a general two-channel fermion-boson model using dynamical DMRG, highlighting the role of correlations and fluctuations in charge dynamics.

Findings

Spectral functions reveal signatures of metal-insulator transition.

Background medium fluctuations significantly affect charge transport.

Correlations and fluctuations interplay controls the system's spectral properties.

Abstract

We analyze the spectral properties of a very general two-channel fermion-boson transport model in the insulating and metallic regimes, and the signatures of the metal-insulator quantum phase transition in between. To this end we determine the single particle spectral function related to angle-resolved photoemission spectroscopy, the momentum distribution function, the Drude weight and the optical response by means of a dynamical (pseudo-site) density-matrix renormalization group technique for the one-dimensional half-filled band case. We show how the interplay of correlations and fluctuations in the background medium controls the charge dynamics of the system, which is a fundamental problem in a great variety of advanced materials.