The nonlinear optical properties of a nematic liquid crystal (NLC 1289) were experimentally studied according to the intensity and polarization of the pump radiation at a wavelength of 1.56 μ m. It is shown that the maximum generation efficiencies of the second and third harmonics correspond to different polarization characteristics of the main radiance. In the investigated range (10 6 … 2 ∙ 10 7 W cm −2 ) the nonmonotonic dependence of the second harmonic intensity on the pump radiance power was demonstrated for the first time. In addition to this, explanation of this effect is also proposed.

中文翻译：

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向列型液晶中的谐波产生

根据在1.56μm波长处的泵浦辐射的强度和偏振，对向列液晶（NLC 1289）的非线性光学性质进行了实验研究。结果表明，二次谐波和三次谐波的最大产生效率对应于主辐射的不同偏振特性。在研究范围（10 6…2∙10 7 W cm -2）中，首次证明了二次谐波强度对泵浦辐射功率的非单调依赖性。除此之外，还建议对此效果进行说明。