Anti-stokes luminescence in a coupled system: A natural consequence of quantum oscillation

Strong anti-Stokes (AS) luminescence from the narrow well (NW) is observed in GaAs/AlxGa1-xAs asymmetric double quantum wells when the wide well (WW) is photoexcited. The normalized efficiency of this AS luminescence decreases slightly with temperature and excitation intensity. Furthermore, the normalized efficiency is of the same order of magnitude with the Stokes transfer rate from the NW to the WW. From these results, we propose quantum oscillation of electron and hole wave functions as the mechanism for the AS luminescence