TiS2,MoS2,WS2/Sb2Te3 mixed nanosheets saturable absorber for dual-wavelength passively Q-switched Nd:GYSGG Laser

We demonstrate the mixed antimony telluride-molybdenum disulfide/tungsten disulfide/titanium disulfide as saturable absorber for efficient passively Q-switching of Nd:GYSGG laser. Sb2Te3-MoS2, Sb2Te3-WS2 and Sb2Te3-TiS2 dispersions with large populations of few layers were prepared by liquid-phase exfoliation. At the pump power of 5 W, dual-wavelength Q-switched operation were obtained with the output power of 0.46W, 0.42 W and 0.35W by using the mixed Sb2Te3-TiS2, Sb2Te3-WS2 and Sb2Te3-MoS2 SAs. The minimum pulse width was 254 ns with a pulse repetition rate of 72.4 kHz was obtained by using the Sb2Te3-MoS2 SA. Obviously, all the mixed saturable absorber shows better SA response. It also allows to generate laser pulse at two different wavelengths simultaneously.