Electronic structure of Ga1-xMnx As probed by four-wave mixing spectroscopy

Four-wave mixing experiments on GaMnAs indicate an increase in the optical response near the band gap with increasing Mn concentration. These findings are attributed to (s,p)-d hybridization, which leads to an enhancement in the density of states in the valence band. Our experiments show that the nonlinearity of the four-wave mixing technique provides a highly sensitive probe for Mn-related changes in the electronic structure of GaMnAs.