含四面体基元复合碱（土）金属硫属中远红外非线性光学晶体研究

项目名称： 含四面体基元复合碱（土）金属硫属中远红外非线性光学晶体研究

项目编号： No.91622107

项目类型： 重大研究计划

立项/批准年度： 2017

项目学科： 数理科学和化学

项目作者： 潘世烈

作者单位： 中国科学院新疆理化技术研究所

项目金额： 80万元

中文摘要： 红外非线性光学晶体是实现中远红外激光输出的关键频率转换器件，具有广泛的应用前景。目前商业化的红外非线性光学晶体由于激光损伤阈值低、双光子吸收强等问题影响了其应用。探索新型红外非线性光学材料的关键是实现大倍频和高激光损伤阈值的平衡。.申请人带领的团队长期从事非线性光学晶体的研究，已设计合成10余种新型红外非线性光学晶体材料。前期研究发现硫属化合物体系中引入易畸变四面体MIVQ4(MIV = Si, Ge, Sn等)基元能够增大形成非中心对称结构的几率；此外，体系中引入碱/碱土金属，有利于提高材料带隙，并增大激光损伤阈值。基于以上策略，本项目以含四面体基元的碱/碱土金属硫属化合物作为切入点，通过结构设计引入非对称性基元，合成出不少于2种中远红外非线性光学晶体，满足大倍频和高激光损伤阈值的平衡，采用第一性原理揭示化合物结构-性能关系，评估新材料的应用前景，为中远红外激光光源的发展提供坚实的基础。

中文关键词： 红外非线性光学晶体；硫属化合物；非线性光学系数；激光损伤阈值；能带

英文摘要： Infrared optical (IR NLO) materials are of great importance in developing IR laser sources by frequency conversion technique, which can be applied widely in many fields. Commercial IR NLO materials are still defective in the high-power laser system owing to their low laser damage thresholds (LDTs) or two-photon absorption. The key problem for the development of new IR NLO materials is to find a suitable balance between high LDTs and NLO coefficient..The research team, led by the applicant, has long been committed to the researches on NLO materials, and have has designed more than 10 new IR NLO crystals. Early research shows that the probability of non-centrosymmetric structures increases when easily distorted MIVQ4 (MIV = Si, Ge, Sn, etc) tetrahedral units are introduced into chalcogenides. It is also found that alkali (or alkaline earth) metal cations are conducive to improving the band gap and LDTs. Based on that, the project will focus on alkali (or alkaline earth) metal chalcogenides containing tetrahedral units, designing non-centrosymmetric units, synthesizing more than two new Mid-Far-IR NLO materials, satisfying the properties requirement of balance between high LDTs and NLO coefficient, revealing the structure-properties relationship by the first-principles method, and evaluating their potential applications. This work will provide the foundation for the development of Mid-Far-IR laser source.

英文关键词： IR nonlinear optical crystals ;Chalcogenides;Nonlinear optical coefficient;Laser damage thresholds ;Band gap