Normal-incidence (001) second-harmonic generation in ordered Ga0.5In0.5P

Despite their strong nonlinear susceptibility (d(14) similar to 120 pm/V for GaAs), LII-V zinc blends semiconductors do not show any second-harmonic generation in the [001] direction. We demonstrate that ordered GaInP does exhibit a nonvanishing second-order coefficient in this direction. We report second-harmonic generation parallel to [001] in ordered Ga0.5In0.5P without domain mixture by transmission and reflection of a 1.42-mum fundamental beam in the transparency region of the material. The susceptibility tensor is fully characterized, and a value of d(22) approximate to 13 pm/V is measured along [001] for an ordering parameter eta = 0.43. The susceptibility as a function of order parameter is investigated by reflected second-harmonic generation at the air/GaInP interface and interpreted in terms of bulk and surface contributions. (C) 2001 Optical Society of America.