Room temperature efficient continuous wave laser diode-end-pumped Tm:YAP laser

High efficient continuous wave Tm:YAP laser end-pumped by laser-diode (LD) is presented in this paper. In experiment, fiber-coupled LD at 795 nm is used to pump the Tm:YAP crystal. The c-cut Tm:YAP crystal with the dimensions of 3 mm×3 mm×7 mm is doped with the 3% Tm³⁺ (atomic fraction). Under the input pump power of 26.2 W, the highest output power reaches 8.12 W with 10% transmittance, and the laser threshold is 4.67 W, corresponding to slope efficiency of 52.1% and the optical conversion efficiency of 31.0%. The free running laser spectrum of Tm:YAP is measured by using a grating monochromator, and the corresponding central wavelength is 1938.2 nm, with full width at half maximum of 2.9 nm.