激光技术, 2007, 31 (3): 0232, 网络出版: 2010-06-03
双轴晶体和频时晶体长度与允许参量分析
The crystal-length and acceptance parameters of SFG with biaxial crystals
非线性光学 双轴晶体 和频 晶体长度 允许参量 温度匹配 nonlinear optics biaxial crystals sum frequency generation crystal-length acceptance parameters KTP KTP LBO LBO temperature matching
摘要
为了分析利用双轴晶体KTP与LBO对1064nm与1319nm激光和频产生589nm钠黄光时的最佳晶体长度和允许参量,对非线性波耦合方程进行推导,得出和频条件下的小讯号解和高转换效率下的稳态解,并由稳态解得出激光功率密度与晶体长度的关系。由相位匹配条件通过级数展开推导出双轴晶体在和频情况下的允许参量,并且给出了晶体的温度匹配条件。结果表明,选择合适长度的晶体,可以使得和频转换效率尽可能的提高,LBOⅠ类匹配和KTPⅡA类匹配优于其它匹配类型,LBO在32.84℃能到达温度匹配。
Abstract
The crystal-length and acceptance parameters of biaxial crystals KTP and LBO used to generate 589nm radiation by means of sum frequency generation(SFG)of 1064nm and 1319nm lasers is analyzed. According to the nonlinear wavecoupling equation of SFG,the exact solutions of low and high power conversion are derived and validated in SFG. On the basis of the solutions,the relationship between power density and crystal-length is given. Acceptance parameters of biaxial crystals are derived and validated from phase matching condition of SFG by means of Taylor expansion. The properties of non-critical phase matching(NCPM)is put forward. It can be seen that sum-frequency conversion efficiency could be increased with appropriate crystal-length,type-ⅠLBO and type-Ⅱ A KTP are much better and NCPM can be attained for LBO at 32.84℃.
刘良清, 袁孝, 吕超. 双轴晶体和频时晶体长度与允许参量分析[J]. 激光技术, 2007, 31(3): 0232. LIU Liang-qing, YUAN Xiao, Lü Chao. The crystal-length and acceptance parameters of SFG with biaxial crystals[J]. Laser Technology, 2007, 31(3): 0232.