Abstract

We report the first time-resolved measurement of the optical nonlinearity formation and of the carrier dynamics in strained piezoelectric multiple quantum wells (MQWs). Strained, [111]-oriented MQWs are attractive for novel optical and electronic device applications^1,2 because they contain large, built-in piezoelectric fields. Exploitation of these materials will depend on a detailed knowledge of the dynamics of photogenerated carriers. In the ultrafast optical experiments that have been performed to date, the shot-to-shot accumulation of carriers, which are long-lived because they are spatially separated at the ends of the MQW structure, has prevented the time resolution of the piezoelectric nonlinearity formation and the elucidation of carrier dynamics.³

© 1994 IEEE