Second-order susceptibility of Ga_05In_05P crystals at 15 μm and their feasibility for waveguide quasi-phase matching

Abstract

The second-order susceptibilities (dij) of both ordered and disordered Ga0.5In0.5P semiconductor crystal films epitaxially grown on GaAs substrates are analyzed. Quasi-phase matching based on periodic order–disorder regions is proposed, and the analysis shows that three of the four independent coefficients, namely, d33′,d31′, and d15′, but not d14′, can be modulated. Maker-fringe experiments were performed at 1.57 µm to measure these coefficients in the deposited crystals. However, the crystal-film orientation allowed a definitive determination of the d14′ coefficient (110 pm/V) only and an upper limit of 60 pm/V for d33′. More-sophisticated experimental techniques are proposed for measuring d33′.