Ti₂CT_x MXene as a Saturable Absorber for Passively Q-Switched Solid-State Lasers

In this work, we successfully fabricated a transmissive saturable absorber (SA) with Ti₂CT_x MXene using the spin-coating method. By inserting the Ti₂CT_x saturable absorber into the diode-pumped solid-state (DPSS) Nd:YAG laser, a stable passively Q-switched operation was obtained near 1.06 μm. At a pump power of 4.5 W, we obtained the shortest pulse duration of 163 ns with a repetition rate of 260 kHz. The corresponding single pulse energy and peak pulse power were 3.638 μJ and 22.3 W, respectively. The slope efficiency and the optical conversion efficiency of the laser were 21% and 25.5%, respectively. To the best of our knowledge, this is the first time that Ti₂CT_x was used in the passively Q-switched solid-state lasers. This work demonstrates that Ti₂CT_x can be a promising saturable absorber for solid-state laser pulse generation.