We propose a new scheme to generate the axisymmetric vector beam. A curved wave plate, designed by using the birefringence properties of a crystal, can generate two different phase distributions with respect to the o-light and e-light, and it then can transform the linearly polarized light into the radial or azimuthal vector beam with the property of rotational symmetry. The above scheme has the advantage of having a simple light path and can be adjusted conveniently. According to Richards-Wolf’s model of the classical vector diffraction, we calculate the distributions of the diffracted electromagnetic field that is illuminated by a hollow Gaussian beam and focused by a lens with high numerical aperture. Results show that the hollow vector beam has a very high intensity and intensity gradient and longitudinal distribution of the electric or magnetic field even if illuminated by the laser with a power of 0.5 W. In addition, real-time adjusted distributions of the photon angular momentum can be generated. This scheme has good application prospects in the manipulations of the microscopic particles.%提出了产生轴对称矢量光束的新方案,根据晶体的双折射性质设计波晶片,形成o光和e光相位板,能够把线偏振光转换为具有旋转对称性的径向或角向矢量空心光束,光路简单,调节方便.应用Richards-Wolf的经典矢量衍射模型,分析计算了空心高斯光束照明、高数值孔径透镜聚焦条件下所产生的衍射光波电磁场分布,结果表明:用功率为0.5 W的激光照明,所获得的矢量空心光束具有很高的光强、光强梯度和很强的纵向电磁场分布,同时还能产生可实时调控的光子角动量分布,方案在微观粒子的操控方面有很好的应用前景.
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