准相位匹配深紫外非线性光学晶体研究进展

Research progress of quasi-phase matching deep-ultraviolet nonlinear optical crystals

深紫外非线性光学晶体是深紫外全固态激光器的关键部件。由于带隙、非线性光学系数、双折射率等因素的限制,除KBe_(2)BO_(3)F_(2)晶体外,现有非线性光学晶体皆难以通过相位匹配实现深紫外激光输出。基于准相位匹配原理实现深紫外激光输出是解决深紫外非线性光学晶体相位匹配问题的新思路。综述了氟化钡镁(BaMgF_(4))晶体、镁方硼石(Mg_(3)B_(7)O_(13)Cl)晶体、硼锗酸镧(LaBGeO_(5))晶体的特性,并介绍了这些晶体基于准相位匹配原理应用于激光输出的研究进展。最后提出了有关准相位匹配深紫外非线性光学晶体研究的建议,并进行了展望。

Deep-ultraviolet(DUV)nonlinear optical(NLO)crystal is a key material for the solid-state lasers to generate DUV coherent lights.Due to the limit of band gap,NLO coefficient and birefringence,the existing NLO crystals are difficult to generate DUV coherent lights by phase matching,except KBe_(2)BO_(3)F_(2) crystal.It’s a new idea to solve the phase matching problem of DUV NLO crystals based on the quasi-phase matching principle.A detailed description of properties of BaMgF_(4) crystal,Mg_(3)B_(7)O_(13)Cl crystal and LaBGeO_(5) crystal,and their applications on the generation of DUV coherent lights based on the quasi-phase matching principle are introduced.Finally,the suggestion and prospect on DUV quasi-phase matching crystals are presented.