双曲正弦平方-高斯光束在单轴晶体中垂直于光轴的传输

Propagation of Sinh-Squared-Gaussian Beams in Uniaxial Crystals Orthogonal to the Optical Axis

基于光束在单轴晶体中的傍轴矢量传输理论,对双曲正弦平方-高斯光束在单轴各向异性晶体中垂直于光轴的传输做了研究,得到了一般的解析传输公式,并用数值计算方法分析了该光束的传输特性。研究表明:由于晶体的各向异性,其原来的偏振特性将不再保持,仅沿x方向偏振的初始场分量衍生出y分量;随着传输距离的增加,非寻常光沿x轴和z轴的偏振场慢变振幅均减小,光强峰值也随之减小。此外,双曲正弦平方-高斯光束在单轴晶体中垂直于光轴传输时,光束参数β取值不同,光强呈现不同的分布状态。

The propagation of sinh-squared-Gaussian beams is investigated and the analytic solutions are obtained by means of an angular spectrum technique in uniaxially anisotropic crystals orthogonal to the optical axis. The propagation properties of the polarization components in crystals originating from sinh-squared-Gaussian beams are discussed with numerical method. The results show that the polarization properties cannot remain the same during propagation due to effects of anisotropic crystals. The field distribution of the beam polarized along the x-direction derives a y component. Along with the increase of the transmission distance, the polarization amplitude of the extraordinary ray along the x axis and the z axis are reduced, and the intensity also decreases. In addition, the propagation of the sinh-squared-Gaussian beams in anisotropic uniaxial crystals orthogonal to the optical axis can be influenced by the parameter β, and different β brings about different intensity distribution.