Optical properties of Gd3+ doped bismuth silicate crystals based on first principles

Bismuth silicate (Bi₄Si₃O₁₂, BSO) crystal, as a nonlinear optical material with excellent optical properties, has a wide range of applications in laser technology, optical communication, and optical information processing. In order to further improve its performance, this study adopts a first principles calculation method based on density functional theory (DFT), selects Gd³⁺ as the dopant, and calculates and explores the changes in optical properties of BSO crystals after doping with 1/12, 1/6, and 1/3Gd³⁺. The calculation results show that the doping of Gd³⁺ changes the electronic structure of BSO crystals, which is manifested in the emergence of new light absorption and emission characteristics, an increase in carrier concentration, an improvement in conductivity, and an enhancement of crystal polarization ability in optical properties. In addition, doping with Gd³⁺ increases the light transmission rate and reduces energy loss of BSO crystals, while releasing more energy during electron band transitions, effectively improving the luminescence performance of BSO crystals. The theoretical research in this article provides an important theoretical basis for understanding the influence of Gd³⁺ doping on the optical properties of BSO, and by optimizing the ratio of Gd³⁺, the optical properties of BSO can be further regulated, opening up new possibilities for its application in optoelectronic devices.