Exciton supersolidity in hybrid Bose-Fermi systems

TL;DR

This paper explores how hybrid Bose-Fermi systems of indirect excitons and electron gases can exhibit supersolid phases with periodic density modulations, including ferromagnetic domains, and discusses their experimental signatures.

Contribution

It demonstrates the emergence of exciton supersolidity in hybrid systems and incorporates spin-dependent interactions to reveal ferromagnetic supersolid phases.

Findings

Roton minimum crossing leads to supersolid formation.

Ferromagnetic supersolid domains are predicted.

Pronounced diffraction maxima suggest experimental detectability.

Abstract

We investigate the ground states of a Bose-Einstein condensate of indirect excitons coupled to an electron gas. We show that in a properly designed system, the crossing of a roton minimum into the negative energy domain can result in the appearance of the supersolid phase, characterized by periodicity in both real and reciprocal space. Accounting for the spin-dependent exchange interaction of excitons we obtain ferromagnetic supersolid domains. The Fourier spectra of excitations of weakly perturbed supersolids show pronounced diffraction maxima which may be detected experimentally.