Broadband near-IR photoluminescence in Ni2+ doped gallium silicate glass–ceramics

Abstract

Broadband and tunable near-infrared (NIR) emission of Ni2+ doped glass–ceramics (GCs) is highly attractive due to their potential to address the challenge of broadband optical amplification in the optical communication band. However, optical activity of Ni2+ in different glass matrix as well as nucleation and crystallization processes in relevant glasses have not been understood fully. Here, broadband NIR photoluminescence was realized through precipitation of LiGa5O8:Ni2+ nanocrystals (NCs) within an alkali gallium-silicate glass matrix by melt-quenching and successive heat treatment. Upon exciting by a 980 nm laser diode, we observed NIR photoluminescence band centered at ~ 1310 nm with full width at half maximum of wider than 300 nm, which was originated from 3T2g(3F) → 3A2g(3F) electronic transition of octahedral coordinated Ni2+ in LiGa5O8 NCs embedded in the GCs. Controlled precipitation of NCs, LiGa5O8:Ni2+ and Ga2O3:Ni2+ were achieved by tailoring the composition of alkali gallium-silicate glass matrix. ab initio molecular dynamics simulation was carried out to clarify the formation of nanophases in the glass system. We confirmed that optical properties of transparent GCs containing Ni2+ NCs can be realized by changing molar percentages of Ga2O3. Our results offer a new insight into the precipitation of NCs in oxide glasses and Ni2+ doped GCs, which may be applicable in the photonic fields, such as optical amplifier and laser.