Shooting mid-infrared nonlinear optical materials with targeted balance performances in ternary d0-transition metal oxides through first-principles

Abstract

Heavy metal oxides are emergent candidates for mid-infrared nonlinear optical (NLO) materials, which might achieve a targeted balance property between the idea band gaps and large NLO coefficients. However, the ternary d0-transition metal oxides as mid-infrared NLO materials have not been systematically investigated by the first-principles. Herein, taking ternary d0-transition metal oxides as a research subject, we collected 94 non-centrosymmetric compounds in the inorganic crystal structure database for screening excellent mid-infrared NLO crystals. Among them, seven compounds are highlighted: HT-La2Ti2O7, ZrMo2O8, Rb3V5O14, β-Tl3VO4, La2MoO6, WO2Cl2, and WOCl4. They have a good balance between the wide band gaps 3.01–4.33 eV and large NLO coefficients of 0.5–0.7 × AgGaS2 (d36 = 13.4 p.m./V), simultaneously possess moderate birefringence of 0.055–0.438 at 1064 nm. This study will provide a guideline for exploring new mid-infrared NLO materials with targeted balance performances in ternary d0-transition metal oxides.