DETERMINATION OF QUADRATIC NONLINEAR-OPTICAL COEFFICIENT OF ALXGA1-XAS SYSTEM BY THE METHOD OF REFLECTED 2ND HARMONICS

The quadratic nonlinear optical coefficient in the AlGaAs system has b een systematically measured as a function of the alloy composition at the fundamental wavelength of 1.064 mum by the method of reflected har monics. The harmonic waves from the thin-film samples are analyzed con sidering various interferences including multiple reflections. The exp erimental results show a reduction of the magnitude of the second-harm onic coefficient with increasing Al content in the AlGaAs system. This tendency is consistent with Miller's rule.