高斯光束通过非线性介质层的限幅效应

本文用数值分析的方法研究了两维高斯光束通过一定厚度的非线性折射介质后在线性空间传播的状态,分析了光束的近场和远场横向强度分布及通过一定孔径光阑的功率.结果表明,在考虑到光束经过非线性介质时,相位与横向分布都会发生变化后,仅在非线性折射效应作用下,在远场就存在限幅效应.在一定的强度范围之内,近场也存在限幅利用的可能性.

Gaussian beam propagation with nonlinear medium limiter

In this paper, a numerical analysis is presented for a laser beam refraction by a bounded nonlinear medium and diffraction during the beam's subsequent free--space propagation using two-dimension Gaussian input profile. The beam's steady-state transverse-field profiles in the near and far-field and power-transfer curves for passing through an aperture are studied. The results show that when beam passes through a nonlinear medium, not only beam's phase, but also its profile are undergoing change. When these bwo factors are taken into consideration, only under the nonlinear refractions effect the power-limiting phenomenon can be observed. In addition, if beam's intensity ia below some level, limiting action effect is also existed in near-field.