深紫外氟化硼酸盐双折射率和折射率色散的性能增益研究

Enhanced nonlinear optical functionality in birefringence and refractive index dispersion of the deep-ultraviolet fluorooxoborates

作为紫外/深紫外非线性光学材料的潜在体系,氟化硼酸盐已引起了该领域的广泛关注.鉴于该类体系中双折射和折射率色散的影响因素尚未明确,我们设计了可能的氟化硼酸盐基团,分析了光学各向异性以探索其对双折射率的影响.通过响应电荷分布各向异性近似,我们进一步证明和筛选了有利于双折射率的微观基团,并系统地探讨了可有效调节双折射率的功能模块.基于发展的折射率色散分析方法,我们发现氟化硼酸盐基团的引入有利于降低该类体系在深紫外区的折射率色散,从而获得较短的相位匹配波长.该研究为功能驱动的材料设计提供了一条途径.

As a promising candidate,the fluorooxoborate has enkindled new explorations of nonlinear optical materials to meet the deep-ultraviolet criteria.However,big challenges and open questions still remain facing this exciting new field,especially the birefringence and dispersion of refractive index which are fundamental parameters for determining the phasematching second harmonic generation wavelength.Here we designed possible anionic groups in fluorooxoborates,and analyzed the optical anisotropy to check its influence on birefringence,which was proved further by the response electronic distribution anisotropy approximation.The functional modules modulating birefringence in fluorooxoborates were explored systematically.We developed an approach for evaluating the behavior of the refractive index dispersions and found that the fluorooxoborates had small refractive index dispersions owing to the introduction of fluorooxoborate modules.Our results demonstrate that fluorooxoborates can be utilized to realize short phase-matching wavelength markedly and offer a path toward novel performance-driven materials design.