Thakur Anita, Berakdar Jamal
Max Planck Institute of Microstructure Physics, Halle, Germany.
Opt Express. 2010 Dec 20;18(26):27691-6. doi: 10.1364/OE.18.027691.
We study the self-focusing and defocusing of a light beam carrying angular momentum (called twisted light) propa- gating in a nonlinear medium. We derive a differential equation for the beam width parameter f as a function of the propagation distance, angular frequency, beam waist and intensity of the beam. The method is based on the Wentzel-Kramers-Brillouin and the paraxial approximations. Analytical expressions for f are obtained, analyzed and illustrated for typical experimental situations.
我们研究了携带角动量的光束（称为扭曲光）在非线性介质中传播时的自聚焦和散焦现象。我们推导了光束宽度参数$f$作为传播距离、角频率、束腰和光束强度函数的微分方程。该方法基于温策尔 - 克拉默斯 - 布里渊近似和傍轴近似。针对典型实验情况，我们获得、分析并说明了$f$的解析表达式。
