Study of nonlinear optical effects in GaN:Mg epitaxial film

The second‐order nonlinear optical coefficients d33, d31, and d15 of GaN:Mg epitaxial film were studied by the standard Maker fringe of an anisotropic medium. The measured d33=−(16.5±1.3) pm/V which is 55 times of the d11 of quartz. The measured ratios of d33/d31 and d31/d15 showed that the crystalline film is close to an ideal wurzite structure. The refractive indices and the dispersive curves of ne, n0 were also determined by TM and TE waveguide mode measurements.