Extreme magnetic modulation of the exciton transfer rate between unequal quantum wells - art. no. 201317

We show that a moderate in-plane magnetic field quenches the Stokes transfe r of excitons between direct and indirect (i.e., type II) quantum wells at low temperatures. The transfer is due to the decay of an exciton in the ini tial well into a free electron-hole pair in the final well. Higher fields o pen, within a narrow range of field, a new dramatically enhanced resonant t ransfer channel for both the Stokes and the anti-Stokes transfer between th e higher-energy direct and lower-energy indirect exciton states. The rates are calculated for GaAs/AlxGa1-xAs quantum wells.