Exciton Liquid in Coupled Quantum Wells

Abstract

Exciton Liquid Excitons, bound states of electrons and holes (states “vacated” by electrons), can be found in semiconductors and have long been predicted to form correlated phases at sufficiently large densities and low temperatures. Stern et al. (p. 55 ) studied the behavior of spatially indirect excitons, which consist of electrons and holes residing in spatially separated, but coupled, quantum wells. The excitons were created through a combination of photoexcitation and electric gating. At high enough laser power and low enough temperatures, a new phase with a distinct photoluminescence signature appeared with behavior consistent with that of a classical liquid of excitons.