Laser-induced grating in ZnO

A simple approach for the calculation of self-diffraction in a thin combined phase and amplitude grating is presented. The third order nonlinearity, the electron-hole recombination time, and the ambipolar diffusion coefficient in a ZnO crystal are measured by means of laser-induced self-diffraction and self-defocusing. It is shown that the index of refraction changes linearly with light intensity and that the intensity dependence of the index of refraction is caused by generation of an electron-hole plasma.<
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