运用空间矢量角谱法,分析了低阶拉盖尔高斯光束(LGB)在空间中的非傍轴矢量传输特性,得到了LGB远场矢量分布的解析式。基于广义Mie散射理论,分析了单个均匀球形粒子对LGB的散射特性。研究结果表明,随着LGB拓扑荷数的增大,光斑中空的面积增大,位于光轴上的微分散射截面减小;随着粒子尺度参数的增大,消光效率因子、散射效率因子和吸收效率因子出现峰值,并且峰值随着拓扑荷数的增大向着粒子尺度增大的方向移动。

The non-paraxial vector propagation characteristics of low order Laguerre-Gaussian beam (LGB) in space are analyzed by the space vector angular spectrum method, and the analytic expression of vectorial far-field distribution of LGB is obtained. Based on the generalized Lorenz-Mie theory, the scattering property of LGB by a single homogeneous spherical particle is analyzed. The research results show that, with the increase of topological charge of LGB, its hollow spot area increases while its on-axis differential scattering cross section decreases. With the increase of particle size, there exist peaks for the absorption, scattering and extinction efficiency factors, meanwhile these peaks shift towards the increase direction of particle size when the topological charge increases.