Effect of hopping and electronic correlation on electron-hole coupling in disordered semiconductor double layer

The effect of the hopping term in the formation of excitons is studied in semiconductor nanostructures where electrons and holes are spatially separated by a potential barrier. We use the lattice gas model where electron-hole system is divided into unit cells with the effective lattice constant being of the order of the exciton size. The exciton density is calculated as a function of the disorder for several fixed values of the hopping integral. It is found that as the value of the hopping integral increases the exciton density decreases rapidly both for weak and strong disorder. Electronic correlation is treated explicitly by introducing repulsion between equally charged carriers and attraction between an electron and a hole from neighboring cells.