The nonlinear propagation characteristics of a radially polarized (RP) beam in uniaxially aligned dye-doped liquid crystal (DDLC) are investigated in experiments and theory. The photothermal effect produces changes in the refractive index of the nonlinear polarization-sensitive medium, in both ordinary and extraordinary directions. The changes promote a self-modulation of the polarization pattern in the incident RP beam as it propagates through the DDLC. The experimental results are explained from theory by modeling the change in the refractive index of the medium. Our results may be applied to spatial polarization modulation, by which an axially symmetric polarized beam is converted into another structured light, such as the full Poincaré beam.

中文翻译：

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单轴取向染料掺杂液晶中径向偏振光束的非线性传播特性

通过实验和理论研究了径向偏振（RP）光束在单轴取向染料掺杂液晶（DDLC）中的非线性传播特性。光热效应使非线性偏振敏感介质的折射率在正常方向和异常方向上都发生变化。当入射的RP光束通过DDLC传播时，这些变化会促进偏振图案在入射RP光束中的自调制。通过对介质折射率的变化进行建模，从理论上解释了实验结果。我们的结果可以应用于空间偏振调制，通过该调制，轴向对称的偏振光束被转换为另一种结构化光，例如完整的庞加莱光束。