Computational design of inorganic nonlinear optical crystals based on a genetic algorithm
Computational design of inorganic nonlinear optical crystals based on a genetic algorithm
复制标题
基于遗传算法的无机非线性光学晶体计算设计
DOI：
10.1039/c4ce01606h
复制
发表时间：
2014-01-01
期刊：
影响因子：
3.1
通讯作者：
Zhang, Yongfan
中科院分区：
文献类型：
--
作者：
Fang, Zhenxing;Lin, Jing;Zhang, Yongfan
基于密度泛函理论的计算结果，提出了一种设计无机非线性光学（NLO）二次谐波晶体的理论方法。在该方法中，一个专门的遗传算法（GA）被开发来搜索已知组成的无机晶体的稳定结构和研究的非中心对称的稳定结构和二阶非线性光学性能，通过计算相应的SHG系数。与常规遗传算法不同，本方法的主要特点是在遗传过程中引入了构建单元的配位方式来构建个体结构，从而显著提高了获得无机晶体稳定结构的效率和成功率。作为典型的例子，两个三元化合物，AgGaS2和LiAsSe2晶体被认为是，除了实验观察到的结构，其他亚稳（或更稳定）相的几何形状和光学性能进行了探索。我们的结果清楚地表明，本方法可以提供一个可行的方法来设计和优化新的无机非线性光学晶体。
Based on the results of density functional theory calculations, a theoretical method to design inorganic nonlinear optical (NLO) crystals for second harmonic generation (SHG) is presented. In this method, a specialized genetic algorithm (GA) is developed to search the stable structures of the inorganic crystal with known compositions and study the noncentrosymmetric stable structures and the second-order nonlinear optical properties by calculating the corresponding SHG coefficients. Unlike normal GA techniques, the main feature of the present method is that the coordination fashions of the building units are introduced to construct the structures of individuals during the GA procedure, which can obviously improve the efficiency and success rate of obtaining the stable structure of the inorganic crystals. As typical examples, two ternary compounds, AgGaS2 and LiAsSe2 crystals are considered, and besides the structures observed experimentally, the geometries and optical performance of other metastable (or more stable) phases have been explored. Our results clearly demonstrate that the present method can provide a feasible way to design and optimize new inorganic NLO crystals.