The photorefractive effect was observed in Fe-doped semi-insulating GaN. We measured the two-beam coupling constant and the grating formation time as a function of pump intensity at a wavelength of 458 nm in reflection geometry. The photorefractive gain coefficient was 0.39 cm-1, and the grating formation time was 7 ms at a pump intensity of 1.0 W/cm2. Besides the refractive index grating, the contribution of an absorption grating was also observed in a two-wave mixing experiment. The coupling constant of the absorption grating was negative and increased with the pump intensity. The origin of the absorption grating was attributed to light-intensity-dependent photochromism. 2009 Elsevier B.V. All rights reserved.
各種検索
サポート
ヘルプ