2.8 μm Laser Realized on a Novel Er:LuYAP Crystal End-Pumped by a 969 nm LD

A novel laser crystal of Er0.15Lu0.1Y0.75AlO3 with high crystalline quality was grown by the Czochralski method. The thermal conductivity, thermal expansion coefficient, and refractive index of the crystal are measured in three axial directions. The absorption, fluorescence spectra, and fluorescence decay curves are also determined. Among them, Er:LuYAP has the highest absorption coefficient at E//b polarization direction. The absorption and fluorescence spectra of Er:LuYAP are broadened slightly. In continuous and pulse modes, maximum average powers of 817 and 1142 mW with slope efficiencies of 17.3% and 17.4%, laser stabilities of 1.8% and 3.2%, and M-2 factors of 1.18/1.19 and 1.67/1.62 are achieved by 969 nm LD end-pumping, respectively. At high power, a single-wavelength laser output at 2799 nm is exhibited. Therefore, the Er:LuYAP crystal is an excellent potential candidate for 2.7-3 mu m tunable and Q-switch laser.