Designing Silicates as Deep‐UV Nonlinear Optical (NLO) Materials using Edge‐Sharing Tetrahedra
Hongping Wu, Bingbing Zhang, Hongwei Yu, Zhanggui Hu, Jiyang Wang, Yicheng Wu, P. Shiv Halasyamani
Abstract
Abstract Discovering new deep‐ultraviolet (DUV) nonlinear optical (NLO) materials is currently a great challenge. The reported DUV NLO materials are almost exclusively borates or phosphates. Silicates—the largest constituent of the earth's crust—are excluded owing to their weak second harmonic generation (SHG) response. We report a silicate, Li 2 BaSiO 4 , with edge‐sharing LiO 4 –SiO 4 tetrahedra that achieves the balance between a short UV absorption edge, below 190 nm, and a large SHG response, 2.8×KDP. The SHG intensity is the largest for silicates without second‐order Jahn–Teller cations, and exceeds that of non‐isomorphic Li 2 SrSiO 4 by more than an order of magnitude. As such Li 2 BaSiO 4 may be seen as a promising DUV‐UV NLO material. This research indicates that edge‐sharing tetrahedra is a new design parameter for discovering new DUV NLO materials.