Intermediate Regime between the Fermi Glass and the Mott Insulator in one Dimension

TL;DR

This paper investigates the transition between Anderson localized and Mott insulating states in disordered one-dimensional spinless fermions, revealing an intermediate liquid-like regime with enhanced conductivity.

Contribution

It identifies and characterizes an intermediate regime where the electron system becomes more liquid before crystallizing, bridging the gap between two known insulating phases.

Findings

Existence of an intermediate liquid-like regime

Enhanced persistent current in the intermediate phase

Transition from localized to crystalline insulating states

Abstract

We consider the ground state reorganization driven by an increasing nearest neighbor repulsion U for spinless fermions in a strongly disordered ring. When U -> 0, the electrons form a glass with Anderson localized states. At half filling, a regular array of charges (Mott insulator) is pinned by the random substrate when U -> \infty. Between those two insulating limits, we show that there is an intermediate regime where the electron glass becomes more liquid before crystallizing. The liquid-like behavior of the density-density correlation function is accompanied by an enhancement of the persistent current.