单轴晶体中杂化偏振矢量涡旋光场的传输特性

Propagation properties of hybridly polarized vector vortex fields in uniaxial crystals

为了实现光场的偏振态调控,对拥有复杂偏振态分布的杂化偏振矢量涡旋光场在单轴晶体中垂直于光轴的传输特性展开研究.基于光束在各向异性单轴晶体中的傍轴矢量传输理论,推导出杂化偏振矢量涡旋光场在单轴晶体中传输的具体表达式.通过数值模拟,得出了不同参数下杂化偏振矢量涡旋光场在单轴晶体中传输的演变规律.结果表明,光束半径、传输距离以及单轴晶体的e光和o光折射率比值对杂化偏振矢量涡旋光场在单轴晶体中的强度分布、偏振态分布、自旋角动量分布以及涡旋相位分布有调节作用.光束半径越小,传输距离越大,单轴晶体的各向异性强度越大,则对杂化偏振矢量涡旋光场的传输特性影响越大.

To realize the manipulation of the polarization states of the light field, the propagation properties of hybridly polarized vector vortex fields with complicated polarization states in a uniaxial crystal whose optical axis was orthogonal to the beam axis were investigated. Based on the theory of the paraxial vector propagation of light beams in anisotropic uniaxial crystals, the exact expressions of the hybridly polarized vector vortex fields propagating in a uniaxial crystal were derived. By numerical simulations, the evolution law of hybridly polarized vector vortex fields propagating in the uniaxial crystal under different influence factors was obtained. The results show that the beam radius, the propagation distance in the crystal, and the refractive index ratio of e light to o light have effects on the distributions of the intensity patterns, the states of polarization, the spin angular momentum and vortex phase of hybridly polarized vector vortex fields in uniaxial crystals. The smaller the beam radius, the greater the propagation distance and the greater the anisotropic intensity of the uniaxial crystal, the greater the influence on the propagation properties of the hybrid polarization vector vortex field.