Q-switched mode-locked all-solid-state Tm:LuAG ceramic laser

Using graphene oxide (GO) by vertical growth method as saturable absorber, an all-solid-state Q-switched mode-locked Tm: Lu₃Al₅O₁₂ (Tm: LuAG) ceramic laser with typical 'X' folded cavity was firstly demonstrated . A 790 nm laser diode (LD) was used as the pumping source. When the pumping power was greater than 8 W, the laser entered a stable Q-switched mode-locked state. When the output mirror was 5%, the maximum output power of continuous light was 714 mW, and the oblique efficiency was 4.94%. When the pumping power reached 16 W, the maximum output power of the laser was 200 mW, the corresponding repetition frequency of mode-locked pulse was 108.7 MHz, and the modulation depth of mode locked pulse in Q-switched envelope was close to 100%. The 2 μm ultrashort pulsed laser has important applications in biomedicine and laser communication.