Correlation-induced metal insulator transition in a two-channel fermion-boson model

TL;DR

This paper studies a new fermion-boson lattice model revealing how charge transport can undergo a quantum phase transition from metal to insulator, with insights into related Mott and Peierls mechanisms.

Contribution

It introduces a novel fermion-boson coupling model and analyzes its groundstate and spectral properties to demonstrate a correlation-induced metal-insulator transition.

Findings

Quantum phase transition from metal to insulator at half-filling

Evolution of band structure in the insulating phase

Connections to Mott and Peierls transition scenarios

Abstract

We investigate charge transport within some background medium by means of an effective lattice model with a novel form of fermion-boson coupling. The bosons describe fluctuations of a correlated background. By analyzing groundstate and spectral properties of this transport model, we show how a metal-insulator quantum phase transition can occur for the half-filled band case. We discuss the evolution of a mass-asymmetric band structure in the insulating phase and establish connections to the Mott and Peierls transition scenarios.