Enhanced 2.0 μm Emission and Lowered Upconversion Emission in Fluorogermanate Glass-Ceramic Containing LaF3:Ho3+/Yb3+ by Codoping Ce3+ Ions

Intense 2.0 μm emission of Ho3+ has been achieved through Yb3+ sensitization in fluorogermanate glass‐ceramic (GC) containing LaF3 pumped with 980 nm laser diode (LD). The observation of concurrent emissions at 538, 650, and 1192 nm points to the additional deexcitation routes based on infrared‐to‐visible upconversion processes and Ho3+:5I6 → 5I8 radiative transition. Comparative investigations of photoluminescent spectra and decay curves have indicated the effective role of Ce3+ ions in enhancing the 2.0 μm fluorescence along with suppressing the occurrence of these concurrent emissions. This would offer a promising approach to develop compact and efficient 2.0‐μm laser systems.