Acousto-Optic Q-Switched Lasing in Tm:YbAG Crystal

Abstract

Acousto-optic Q-switched lasing in the crystal Tm:Yb₃Al₅O₁₂ (Tm:YbAG) pumped at the wavelength of 1.678 µm into the ³F₄−³H₆ thulium transition is investigated. The highest differential laser efficiency was 13%. The laser pulse energy was as high as 100 µJ at the optimum pulse repetition rate of 6.7 kHz and monopulse duration of 45 ns. The lifetime of the excited Tm³⁺ ion under intense lasing is experimentally estimated. The effect of upconversion processes on lasing is analyzed.