1560-nm Acousto-Optic Q-Switched and Intracavity Frequency Doubling Laser Performances of Er:Yb:RAl3(BO3)4 (R = Y and Lu) Crystals

Laser oscillations except for 1560 nm were suppressed and efficient acousto-optic Q-switched pulse lasers at a single wavelength of 1560 nm were realized in Er:Yb:RAl3(BO3)(4) (R = Y and Lu) crystals by a special design of the cavity mirror transmissions, when a 970-nm diode laser with a 2% duty cycle was used as the pump source. At an absorbed pump power of 13.5 W and a pulse repetition frequency of 1 kHz, 400-mu J pulse energy with a width of 155 ns and 580-mu J pulse energy with a width of 110 ns were achieved in Er:Yb:YAl3(BO3)(4) and Er:Yb:LuAl3(BO3)(4) crystals, respectively. Furthermore, intracavity frequency doubling 780-nm Q-switched pulse lasers were realized by using a KTP nonlinear optical crystal. The pulse energy and width were 30 mu J and 80 ns for Er:Yb:YAl3(BO3)(4) crystal and 50 mu J and 68 ns for Er:Yb:LuAl3(BO3)(4) crystal, respectively.