Jalali Amir A, Rybarsyk James, Rogers Evan
Electro-Optics Technology Inc., Traverse City, Michigan 49684, USA.
Opt Express. 2013 Jun 3;21(11):13741-7. doi: 10.1364/OE.21.013741.
An analysis is presented of a TGG crystal rod under high power laser operation. A semianalytical thermal analysis is investigated to obtain the temperature profile and thermal lensing effect in a TGG crystal upon incidence of a high power laser light. By solving the heat transfer equation for the TGG crystal and taking the Gaussian beam transverse intensity profile as the heat source, the optical path difference due to induced thermal effects was obtained. Moreover, a detailed model for the dependence of thermal lensing and beam degradation which takes into account up to the fifth-order spherical aberration is presented. Based on this model, it is shown that up to a critical value of the beam power the degradation of the beam is not significant. The experimental results on thermal lensing and degradation on beam quality of a high power laser passing through a TGG crystal rod are in agreement with the main results from our model.
本文对高功率激光运行下的TGG晶体棒进行了分析。研究了一种半解析热分析方法，以获得高功率激光入射时TGG晶体中的温度分布和热透镜效应。通过求解TGG晶体的热传递方程，并将高斯光束横向强度分布作为热源，得到了由热效应引起的光程差。此外，还提出了一个详细的热透镜和光束退化依赖模型，该模型考虑了高达五阶的球差。基于该模型，结果表明，在光束功率达到临界值之前，光束的退化并不显著。高功率激光通过TGG晶体棒时的热透镜和光束质量退化的实验结果与我们模型的主要结果一致。
