Energy Transfer of Excitons and Electron-Hole Plasmas between Quasi-two-dimensional Semiconductor Layers

We study the energy transfer mechanisms of excitons and electron-hole plasmas between two quasi-two dimensional (2D) semiconductor quantum wells. It is shown that dipolar (i.e., Foerster) energy transition (ET) mechanism dominates at a short distance while photon-mediated ET mechanism plays a more important role for transfer over a long distance. The magnitude and the dependence of the transfer rates of plasmas and excitons on the temperature, the well-to-well distance, and the density are compared for both ET mechanisms. The spatial dependence of the 2D-2D transfer rates will be compared with that of the ET rate between two quantum dots.