激光与光电子学进展, 2019, 56 (16): 161401, 网络出版: 2019-08-05
利用Cr 4+∶YAG晶体的各向异性提高输出激光消光比的实验研究
Improving Extinction Ratio of Output Laser with Anisotropy of Cr
4+∶YAG Crystal
摘要
为了研究不同切割方向Cr
4+∶YAG晶体的各向异性对激光器输出偏振特性的影响,采用1064 nm线偏振脉冲光作为测试光源,从输入光强功率密度、晶体初始透过率和晶体切割方向3个方面,对Cr
4+∶YAG晶体的各向异性进行实验研究。结果表明:在一定功率密度范围内,功率密度越高,Cr
4+∶YAG的各向异性越明显;Cr
4+:YAG的初始透过率越低,各向异性越明显;相同功率密度下,[110]切割方向的Cr
4+∶YAG在某一方向上的可饱和透过率大于[100]切割方向的Cr
4+∶YAG的透过率。分别选取[110]和[100]切割方向的Cr
4+∶YAG作为调Q 晶体,搭建808 nm LD抽运Nd∶YAG/Cr
4+∶YAG被动调Q 固体激光器,得到[110]切割方向Cr
4+∶YAG的输出激光消光比大于[100]切割方向Cr
4+∶YAG的输出激光消光比。
Abstract
To explore the effect of the anisotropy of different cut directions of Cr
4+∶YAG crystals on the polarization characteristics of laser output,the anisotropy of Cr
4+∶YAG crystal is studied experimentally using 1064-nm linearly polarized pulsed light as the test light source. In the experiment, the input light power density, initial transmittance, and crystal cutting direction are considered. The experimental results demonstrate that within a certain range of power density, the higher the power density is, the more obvious the anisotropy of Cr
4+∶YAG is. The results also show that anisotropy is obvious with low initial transmittance of Cr
4+∶YAG. Under the same power density, the saturation transmittance of [110]-cut Cr
4+∶YAG is greater than that of [100]-cut Cr
4+∶YAG in a certain direction. The [110]-cut and [100]-cut Cr
4+∶YAG crystals are used as saturable absorbers for an 808-nm LD pumped passively Q-switched Nd∶YAG/Cr
4+∶YAG solid laser, and the experimental results demonstrate that the extinction ratio of the output laser with [110]-cut Cr
4+∶YAG is greater than that with [100]-cut Cr
4+∶YAG.
张思, 汪楠, 王旭葆, 林学春. 利用Cr 4+∶YAG晶体的各向异性提高输出激光消光比的实验研究 [J]. 激光与光电子学进展, 2019, 56(16): 161401. Si Zhang, Nan Wang, Xubao Wang, Xuechun Lin. Improving Extinction Ratio of Output Laser with Anisotropy of Cr 4+∶YAG Crystal [J]. Laser & Optoelectronics Progress, 2019, 56(16): 161401.