Structural and Luminescence Properties of Transparent Nanocrystalline ZrO₂:Er³⁺ Films

The structural and luminescence properties of nanocrystalline ZrO₂:Er³⁺ films are reported. Transparent nano-ZrO₂ crystalline films doped with Er³⁺ have been prepared using a wet chemistry process. An intense room-temperature emission at 1527nm with a full width at half-maximum of 46nm has been observed, which is assigned to the ⁴I_13/2 → ⁴I_15/2 intra-4fⁿ electric transition of Er³⁺. Correlations between the luminescence properties and structures of the nanocrystalline ZrO₂:Er³⁺ films have been investigated. Infrared-to-visible upconversion occurs simultaneously upon excitation of a commercially available 980-nm laser diode and the involved mechanisms have also been explained. The results indicate that the nanocrystalline ZrO₂:Er³⁺ films might be suggested as promising materials for achieving broadband Er³⁺-doped waveguide amplifiers and upconversion waveguide lasers.