Localization and interaction of indirect excitons in GaAs coupled quantum wells (original) (raw)

We introduced an elevated trap technique and exploited it for lowering the effective temperature of indirect excitons. We observed narrow photoluminescence lines which correspond to the emission of individual states of indirect excitons in a disorder potential. We studied the effect of exciton-exciton interaction on the localized and delocalized exciton states and found that the homogeneous line broadening increases with density and dominates the linewidth at high densities. PACS numbers: 73.63.Hs, 78.67.De Disorder is an intrinsic feature of solid state materials. It forms due to the spatial inhomogeneity of the sample. In other systems, such as liquid Helium or cold atomic gases, disorder can be artificially introduced. The behavior of particles in a disorder potential is a subject of intensive research. The studies have concerned electrons in semiconductors and superconductors, liquid Helium in a porous media, and cold atomic gases in a disorder potential formed by optical patterning, see e.g. .