Opt Lett. 2014 Feb 15;39(4):1101-4. doi: 10.1364/OL.39.001101.
We experimentally demonstrate the generation of radially polarized Bessel-Gaussian beams from a c-cut Nd:YVO₄ laser with a hemispherical cavity configuration by proper mode control. The output beam has an annular-shaped intensity distribution with radial polarization. When the beam is focused, the intensity pattern changes to a multi-ring, which is a typical characteristic of the lowest transverse mode of vector Bessel-Gaussian beam. Higher-order modes of vector Bessel-Gaussian beam are also observed from the same cavity by slightly changing the cavity alignment. The experimental results show a good agreement with the simulation results for both focal and far fields. The present method is a simple and direct way for generating vector Bessel-Gaussian beams.
我们通过适当的模式控制,从具有半球形腔配置的 c 切 Nd:YVO₄ 激光器实验演示了径向偏振贝塞尔-高斯光束的产生。输出光束具有环形强度分布和径向偏振。当光束聚焦时,强度图案会变为多环,这是矢量贝塞尔-高斯光束的最低横模的典型特征。通过稍微改变腔的对准,也可以从同一腔中观察到矢量贝塞尔-高斯光束的高阶模式。实验结果与远场和近场的模拟结果吻合较好。本方法是产生矢量贝塞尔-高斯光束的一种简单直接的方法。