2-μm passive Q-switched Tm:YAP laser with SnSe2 absorber

Few-layer SnSe2 was successfully fabricated by liquid phase exfoliation method. A passive Q-switched Tm:YAP laser at the wavelength of 1940 nm was demonstrated by using SnSe2 saturable absorber (SA). Under absorbed pump power of 4.9 W, 400 mW Q-switched was achieved with the pulse width of 1.29 μs and the repetition rate of 109.77 kHz. The results indicate the promising potential of SnSe2 nanosheets as SA to achieve efficient pulsed lasers at around 2 μm.