轴棱锥聚焦涡旋光束获得高阶贝塞尔光束

Generation of high-order Bessel beams by focusing vortex beams with an axicon

采用轴棱锥聚焦涡旋光束,获得了高阶贝塞尔(Bessel)光束。首先,从理论模拟了涡旋光束经过轴棱锥聚焦后所获得的聚焦光强分布,结果表明,涡旋光束经过轴棱锥聚焦后可获得高阶贝塞尔光束。并且所获得的高阶贝塞尔光束的阶数与涡旋光束的拓扑电荷数相同。进而,从实验获得高阶贝塞尔光束,并且采用不同锥角的轴棱锥对涡旋光束进行聚焦,研究轴棱锥的锥角对高阶贝塞尔光束的影响,结果表明,在轴棱锥相应的最大准直距离内所得到的高阶贝塞尔光束与理论计算结果相当吻合。

In this paper the generation of highorder Bessel beams by focusing the vortex beams with an axicon is presented.The intensity distribution of vortex beams after being focused by the axicon was simulated.It is shown that after being focused by the axicon,a vortex beam can be converted into the high order Bessel beam.Moreover,the order of the Bessel beam is equal to the topological charge number of the vortex beam.The generation of the high order Bessel beam was also experimentally investigated.The axicons with different cone angles were employed to focus the vortex beam,and the influence of cone angle of the axicon on the high order Bessel beam was investigated.The experimental results show that in the maximum distance of non-diffraction zone of the axicon,the achieved high order Bessel beam coincides with the theoretically calculated results.