Growth, Structural, First-Principles Calculations and Spectroscopic Characterization of Undoped and Er³⁺-Doped NaSrY(MoO₄)₃Disordered Laser Crystals

This study reports the growth of NaSrY(MoO₄)₃(NSYM) and xEr³⁺:NaSrY_1–x(MoO₄)₃disordered single crystals using the top-seeded solution growth (TSSG) method and for the first time presents the structural characteristics and spectroscopic properties of these crystals. Single-crystal analysis indicates that the crystals belong to the tetragonal system with space group I4₁/a. Due to the random occupation of Na⁺, Sr²⁺, and Y³⁺cations at the same lattice sites in a 1:1:1 stoichiometric ratio, Er³⁺doping further enhances the structural disorder, resulting in significant inhomogeneous broadening of the absorption and emission spectra. Key parameters such as refractive index distribution, band structure, density of states, and elastic constants were calculated based on density functional theory (DFT). Judd–Ofelt theory was used to quantitatively analyze the spectral parameters of Er³⁺ions. The agreement between experimental and theoretical analyses indicates that Er:NSYM crystals, with their unique spectroscopic properties, have significant potential as gain media in tunable laser applications.