▎ 摘　　要

By simultaneously using a multi-walled carbon nanotube (MWCNT) and a monolayer graphene saturable absorber (SA) in the cavity, a laser-diode-pumped dual-loss-modulated passively Q-switched Tm:LuAG laser at 2 mu m is demonstrated for the first time. In comparison with the singly passively Q-switched laser with MWCNT or monolayer graphene SA, the doubly passively Q-switched laser with both MWCNT and monolayer graphene SA can generate shorter pulse width and higher peak power. A maximum pulse width compression ratio of 2.8 and a highest peak power enhancement factor of 4 were obtained at the incident pump power of 5.8 W, respectively. The experimental results show that the dual-loss modulation is an efficient method to compress the pulse widths and improve the peak powers of the Q-switched lasers at 2 mu m.