Excitation polarization dependence of optical coupled exciton states in a single coupled quantum dot molecule

Abstract

The optically coupled exciton states have been investigated in terms of power dependent photoluminescence at the coupled GaAs quantum dots, which were laterally coupled along the [1 (1) over bar0] direction. The power dependent photoluminescence results are compared with two different excitation directions which are parallel to the direction of [1 (1) over bar0] and [110]. In coupled direction along the [1 (1) over bar0] direction, the power dependent redshift and coupled biexciton are observed, a fact that may be attributed to optical couplings via dipole-dipole interactions. Also, the redshift of excitons was manifested based on theoretical model.