Luminescence and energy transfer in Er3+/Nd3+ ion-codoped Ge–In–S–CsBr chalcohalide glasses

This study investigates the emission properties of the Er3+/Nd3+ ions codoped 70GeS2–10In2S3–20CsBr chalcohalide glasses. The vacuumed melt-quenching technique is employed to synthesize the glasses. The absorption spectra, upconversion and near-IR emission spectra as well as fluorescence decay curves are collected. With the increasing concentration of Er3+ ions, the lifetimes at 1073 nm for Nd3+ ions decrease from 538 to 420 μs under 808 nm excitation. Meanwhile, the lifetimes at 1540 nm for Er3+ ions decrease from 245 to 214 μs with the increasing concentration of Nd3+ ions. The emission spectra and lifetimes show that energy transfer exists between the Nd3+ and Er3+ ions. The luminescence and detailed energy transfer mechanisms are schematically proposed.