Efficient CW Dual-Wavelength and Passively  $Q$ -Switched Tm:LuAG Lasers
Efficient diode-pumped Tm:LuAG lasers operating in continuous wave, dual-wavelength,and passive Q-switching regimes have been demonstrated. A maximum output power of 4.42 W with a beam quality of M2 ≤1.45 at 2021.2 nm was obtained, corresponding to a slope efficiency of 49.5%. Using a birefringent quartz plate, the Tm:LuAG laser emitted the highest output power of 2.3 W at dual-wavelength of 2022 and 2030 nm. With a SWCNT-SA employed as saturable absorber, passively Q-switched Tm:LuAG laser was realized, which generated the shortest pulses of 405 ns at 2021.6 nm and a maximum single pulse energy of 40.6 μJ at 2019.7 nm.