Structure and spectral properties of Dy³⁺ doped CaYAlO₄ single crystal

A 2 at.% Dy³⁺: CaYAlO₄ single crystal was grown successfully. The electronic structures of Ca²⁺/Y³⁺ mixed sites in CaYAlO₄ were investigated using first-principles based on density functional theory. The effects of Dy³⁺ doping on the structural parameters of host crystal were studied using XRD pattern. The optical properties including absorption spectrum, excitation spectrum, emission spectra and fluorescence decay curves were thoroughly investigated. The results show that the Dy³⁺: CaYAlO₄ crystal could be pumped by the blue InGaN and AlGaAs or 1281 nm laser diodes. Furthermore, an intense 578 nm yellow emission was obtained directly under excitation at 453 nm, meanwhile, evident mid-infrared light emitting was observed by 808 or 1281 nm laser excitation. The fitted fluorescence lifetimes of ⁴F_9/2 and ⁶H_13/2 levels were about 0.316 ms and 0.038 ms, respectively. It can be concluded that this Dy³⁺: CaYAlO₄ crystal could simultaneously act as a promising medium for both solid-state yellow and mid-infrared laser outputs.