高功率单频LBO腔内倍频461nm钛宝石激光器  

High-Power Single-Frequency 461 nm Generation from an Intracavity Doubling of Ti∶Sapphire Laser with LBO

作　　者：李慧娟[1] 张淼[1] 李凤琴[1] 

机构地区：[1]山西大学光电研究所量子光学与光量子器件国家重点实验室,山西太原030006

出　　处：《中国激光》2016年第3期13-19,共7页Chinese Journal of Lasers

基　　金：国家青年基金(11504220);山西省青年基金(2015021022)

摘　　要：利用全固态单频绿光激光器作为抽运源抽运钛宝石晶体,采用六镜环形谐振腔结构。在谐振腔内插入I类临界相位匹配的LBO晶体进行腔内倍频,TGG晶体和宽带半波片(HWP)组成的光学单向器保证单频运转。加入三片厚度分别为1、2、4 mm的双折射滤波片组合和一片0.25 mm的控温标准具片作为调谐元件,实现了高功率单频可调谐461 nm蓝光钛宝石激光器。在14 W的抽运功率下,选取LBO倍频晶体的最佳长度为7.3 mm时,获得了最大功率为1.02 W的单频可调谐蓝光输出,中心波长为460.86 nm,3 h内其长期稳定性优于±1.3%,光束质量得到了明显的改善,其M2因子优于1.59,蓝光最大调谐范围为20 nm。A high-power single-frequency 461 nm light by intracavity doubling of Ti：sapphire laser is designed and built. An astigmatically compensated double-folded resonator with six mirrors is employed to give two tight-focus regions, where Ti：sapphire and doubling crystals are located respectively. A type-I critical phase-matched LBO, an optical diode composed with a TGG crystal and a broadband half wave plate （HWP） are placed inside the resonator for the intracavity frequency doubler and forcing the laser to operate unidirectionally. Three birefringent filters with different thicknesses of 1, 2, 4 mm and a temperature controlled etalon with thickness of 0.25 mm are inserted in the cavity to tune the fundamental wavelength of 461 nm Ti∶sapphire laser. With the pump power of 14 W and an optimized LBO crystal with the length of 7.3 mm, the tunable single-frequency second harmonic output of 1.02 W at 460.86 nm is obtained. The peak-to-peak fluctuation of the power is less than ± 1.3% within 3 h. The measured beam quality of M2 and the tuning range of blue laser are better than 1.59 and 20 nm, respectively.

关 键 词：激光器 钛宝石激光器 高功率 阈值 腔内倍频 

分 类 号：O436[机械工程—光学工程]