Two-color picosecond experiments on anti-Stokes photoluminescence in GaAs/AlGaAs asymmetric double quantum wells

Abstract

Two-color photoluminescence experiments are performed on the anti-Stokes photoluminescence in GaAs/AlGaAs asymmetric double quantum wells. Direct evidence for forbidden absorption is shown, and its many intriguing aspects, particularly the role of long-lived defects, are revealed. Our experiments shed light on the ongoing controversies between many different models.