Supersolidity in electron-hole bilayers with a large density imbalance

TL;DR

This paper investigates electron-hole bilayers with extreme density imbalance, providing evidence for FFLO phase existence and discovering a supersolid phase formed by exciton condensation.

Contribution

It introduces a variational wave function approach to demonstrate FFLO phase presence and identifies a novel supersolid phase in highly imbalanced electron-hole bilayers.

Findings

Evidence for FFLO phase in electron-hole bilayers.

Formation of a two-dimensional exciton supersolid.

Strong theoretical support for supersolidity in imbalanced systems.

Abstract

We consider an electron-hole bilayer in the limit of extreme density imbalance, where we have a single particle in one layer interacting attractively with a Fermi liquid in the other parallel layer. Using an appropriate variational wave function for the dressed exciton, we provide strong evidence for the existence of the Fulde-Ferrell-Larkin-Ovchinnikov (FFLO) phase in electron-hole bilayers with a large density imbalance. Furthermore, within this unusual limit of FFLO, we find that a dilute gas of minority particles forms excitons that condense into a two-dimensional "supersolid".