Airy光束在Kerr介质中的传输特性

Propagation properties of Airy beams in Kerr medium

通过对非线性薛定谔方程的研究,得出Airy光束在Kerr介质中的崩塌功率及有效束宽演化的解析表达式。经过数值计算发现,Airy光束在聚焦的Kerr介质中,其主瓣在开始传播时始终是会聚的;当输入功率小于临界崩塌功率时,Airy光束主瓣的中心部分出现局部崩塌。在不同的Kerr介质中,Airy光束的形状和传输轨道均能保持不变,如同在自由空间中传播,但光场大小的分布,随着不同的Kerr介质会发生改变:在Kerr的聚焦介质中,光场向中心聚焦;而在散焦的Kerr介质中,光场会发散。

The effects of Kerr nonlinearity on Airy beams are investigated using the nonlinear Schrdinger equation.Based on the method of moments,the evolution of effective beam width is analytically obtained as well as the collapse power for Airy beams propagating in Kerr medium.Numerical simulations indicate that central parts of the major lobe of Airy beams give rise to initially radial compression during propagation even though the root-mean-square beam width broadens.Partial collapse of the central parts will appear for input power below the threshold for a global collapse.The field distributions of Airy beams are different during propagation in different media while the profiles and trajectories of the beams still remain invariant.In focused Kerr medium,the field of Airy beams is focused on center.In disfocused Kerr medium,it is dispersed.