紫外全固态激光器在激光技术方面具有重要的应用，其发展受到非线性光学晶体的限制。目前商业化的非线性光学晶体材料的综合性能无法满足紫外应用需求。发展同时具有短紫外吸收边，较大倍频系数和适中双折射率的新型紫外非线性光学晶体材料至关重要。研究团队前期已在氟化硼酸盐体系中获得系列性能优异的新非线性光学晶体材料，证明该体系能够满足“带隙-非线性光学系数-双折射率”平衡关系。针对发展新型紫外全固态激光器的迫切需求，本项目以氟化硼酸盐非线性光学晶体为研究对象，系统开展新晶体的机理研究、晶体生长和激光性能评估。本项目实施拟提供一种新型紫外非线性光学晶体（倍频效应>1KDP@1064nm；双折射率>0.07@532nm），加工高质量的晶体器件（3mm×3mm×6mm，平面度< λ/2@633nm，表面光洁度>20/10S/D），实现紫外激光倍频输出，进一步推动紫外全固态激光器光源的发展。

All solid state ultraviolet (UV) laser source stimulates great research interests because of its wide range of applications in advanced photonic technologies. Such UV light generation in solid-state lasers largely depends on the performance of nonlinear optical (NLO) materials. However, commercial available NLO materials cannot satisfy the need of UV laser application. Therefore, it is important to develop new UV NLO materials that possess short UV absorption edge, large NLO coefficient, and suitable birefringence. Our research group has obtained many new NLO materials with excellent NLO properties in fluorooxoborate system and found that crystals in this system would be ideal candidates that balance the “bandgap-NLO coefficient- birefringence” relationship. In this project, in order to develop new UV laser, our research team (lead by Xinjiang Technical Institute of Physics & Chemistry. CAS, and together with Tianjin University of Technology and Academy of Opto-Electronics, CAS) will carry out the design, synthesis, and evaluation of new UV NLO crystals based on fluoroborates system. This project aims at providing a new UV NLO crystal (SHG response >1 × KDP@1064 nm, and birefringence >0.07@532 nm) and crystal devices with high quality (3mm×3mm×6mm，flatness < λ/2 @ 633 nm, surface fineness > 20/10 S/D), realizing frequency-doubled UV laser output, and further accelerating the development of UV laser source.