Manipulation and Improvement of Autofocusing Properties for Circular Butterfly Beams
Yiming Cai, Juntao Hu, Zhuo Sun, Yanping Lan, Houan Teng, Yixian Qian
Abstract
Abstract A new class of (2+1)‐dimensional circular butterfly beams (CBBs) is first demonstrated based on high‐dimensional butterfly catastrophes. The intensity of CBBs increases abruptly by two orders of magnitude right before they propagate to the focal plane, implying that they possess an abruptly autofocusing (AAF) ability induced by accelerating properties. The autofocusing performance can be further improved by introducing vortices. Owing to the flexibility of high‐dimensional catastrophes, butterfly beams exhibit diverse optical light structures; thus, the focal length, focal intensity, and light field structures of CBBs are tunable. Experimental results are consistent with numerical findings. Therefore, CBBs enrich the family of AAF beams and will be advantageous for optical micromachining, medical treatments, optical tweezers, and nonlinear processes.