Abstract

Recent studies of the transient behavior of absorption saturation in low temperature Multiple Quantum Wells (MQW) samples have revealed a surprisingly fast recovery of absorption (within 10 ps at 15 K) after excitation by intense ultrashort light pulses¹. This has been attributed to the effect of the large stimulated recombination rate caused by amplified spontaneous luminescence guided along the MQW structure, as confirmed by streak camera observations of the edge-emitted luminescence¹, and by measurements of time-resolved luminescence spectra with subpicosecond resolution². This effect could be used to increase the speed of optical gates based on absorption saturation or carrier-induced nonlinear refraction, but a more complete understanding of the mechanisms involved is clearly needed in order to evaluate the interest of this approach.

© 1988 Optical Society of America