Abstract

Two-photon transitions near the absorption edge in a semiconductor multiple guantum well (MQW) structure are important because they provide information about the energy states involved in the forbidden direct transitions^1,2 and the induced Kerr-like optical nonlinearity has potential for ultrafast nonlinear switching applications^3,4. In the TE polarization mode (the polarization is perpendicular to the MQW growth direction), there are no distinct exciton features because the two-stage transition includes an interband transition and an intraband transition whose final state is a 2P exciton. In the TM polarization mode (the polarization is parallel to the MQW growth direction), distinct exciton features are expected because the intraband transitions are forbidden and intersubband transitions are allowed. In this situation, 1S excitons can be the final states for two-photon transitions.

© 1993 Optical Society of America