CSIR National Laser Centre, Pretoria 0001, South Africa.
Opt Lett. 2013 Sep 1;38(17):3429-32. doi: 10.1364/OL.38.003429.
Nondiffracting vector Bessel beams are of considerable interest due to their nondiffracting nature and unique high-numerical-aperture focusing properties. Here we demonstrate their creation by a simple procedure requiring only a spatial light modulator and an azimuthally varying birefringent plate, known as a q-plate. We extend our control of both the geometric and dynamic phases to perform a polarization and modal decomposition on the vector field. We study both single-charged Bessel beams as well as superpositions and find good agreement with theory. Since we are able to encode nondiffracting modes with circular polarizations possessing different orbital angular momenta, we suggest these modes will be of interest in optical trapping, microscopy, and optical communication.
非衍射矢量贝塞尔光束由于其非衍射特性和独特的高数值孔径聚焦特性而备受关注。在这里，我们通过仅使用空间光调制器和称为 q 板的各向异性双折射板的简单步骤来演示它们的产生。我们扩展了对几何和动态相位的控制，以对矢量场进行偏振和模态分解。我们研究了单电荷贝塞尔光束以及它们的叠加，并与理论吻合良好。由于我们能够用具有不同轨道角动量的圆偏振编码非衍射模式，因此我们认为这些模式将在光学捕获、显微镜和光通信中具有吸引力。
