Passively Q-switched mode-locked Nd:GdTaO4 laser by rhenium diselenide saturable absorber operated at 1066 nm

We demonstrate the fabrication process of rhenium diselenide (ReSe2) saturable absorber (SA) and its application for passively Q-switched mode-locked Nd:GdTaO4 laser. The characterization of this SA was described in detail. The modulation depth of the ReSe2 nanosheet was 11.4%. Under the pump power of 4 W, the maximum average output power of 0.209 W was obtained with optical conversion efficiency of 5.2%. The estimated shortest mode-locked pulse width was about 447 ps. Our results show that the shorter pulse width can be obtained by ReSe2 SA at 1066 nm.