Two-photon absorption of neodymium laser radiation in gallium arsenide

Abstract
We have studied the interaction of picosecond pulses from a Nd : glass laser with GaAs. The experimental data at incident powers up to ∼30 GW/cm2 can be satisfactorily explained in terms of two‐photon absorption with β=0.015±0.005 cm/MW. The results are discussed in connection with the discrepancies existing in the literature about the experimental values of β. Their implications for the existence of self‐induced transparency effects in GaAs are also briefly pointed out.