Electric-field-induced exciton transport in coupled quantum well structures

Abstract
We report a conceptionally new approach to achieve electrostatically induced transport and confinement for spatially indirect excitons. Experimentally, exciton transport is demonstrated in an electric-field-tunable GaAs/AlAs coupled quantum well structure, which is configured as a three-terminal device. In spatially resolved photoluminescence experiments, it is shown that indirect excitons experience a drift field, which is given by an electrostatically induced band-gap gradient in the plane of the coupled quantum well structure.