Abstract

Systematic polarization-dependent studies of degenerate four-wave mixing (DFWM) on the 2-D exciton in GaAs quantum wells have revealed the strong influence of exciton/exciton interaction on the nonlinear response.^1-3 There are still, however, open questions concerning whether true bound biexciton states provide a significant contribution to the nonlinear response or whether excitation-induced dephasing processes can completely explain the experimental DFWM signals. Evidence for the formation of biexciton states in GaAs QWs and their important role in the explanation of the nonlinear-optical properties has been independently derived from pump-probe studies³ and the observation of an additional peak on the low-energy wing of the time-integrated 2-D exciton photoluminescence line.⁵

© 1994 Optical Society of America