By measuring the ultraviolet-light-induced absorption in Sc-, Mg- and Zn-doped near-stoichiometric lithium niobate (LiNbO[Formula: see text], we find that the steady-state ultraviolet-light-induced absorption coefficient changes with respect to the doping concentration. There is a strong ultraviolet-light-induced absorption when doping concentration is below its photorefractive threshold and a really weak absorption when the crystal is highly doped. We also use OH[Formula: see text] infrared absorption spectra and the transmitted light spot distortion method to verify the result. Thus, we can determine if the doping level in these doped near-stoichiometric LiNbO3 crystals is above or below their photorefractive threshold by measuring the ultraviolet-light-induced absorption.

中文翻译：

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Sc-、Mg- 和 Zn 掺杂的近化学计量 LiNbO3 中的光诱导吸收和光学损伤

通过测量 Sc-、Mg- 和 Zn 掺杂的近化学计量铌酸锂（LiNbO[公式：见正文]）的紫外光诱导吸收，我们发现稳态紫外光诱导的吸收系数随掺杂浓度。当掺杂浓度低于其光折变阈值时，会出现强烈的紫外光诱导吸收，而当晶体高度掺杂时，会出现非常弱的吸收。我们还使用 OH[公式：见正文]红外吸收光谱和透射光点畸变法来验证结果。因此，我们可以确定这些掺杂的近化学计量的 LiNbO 中的掺杂水平是否3通过测量紫外光诱导的吸收，晶体是否高于或低于其光折变阈值。