Two-dimensional WS2 nanosheet based passively Q-switched Nd:GdLaNbO4 laser.

Highlights • A novel Nd:GdLaNbO 4 mixed crystal was investigated and used as laser medium. • A two-dimensional WS 2 nanosheet was prepared and served as saturable absorber. • The Q-switched Nd:GdLaNbO 4 laser based on WS 2 was demonstrated for the first time. Abstract In this paper, we present a diode-pumped passively Q-switched laser based on a novel Nd:Gd 0.89 La 0.1 NbO 4 mixed crystal and two-dimensional (2D) tungsten disulfide (WS 2) saturable absorber. After the optimization of the laser parameters, a maximum continuous-wave (CW) output power of 4.37 W with a slope efficiency of 42% was obtained, which is the highest output power to the best of our knowledge. Utilizing the saturable absorption characteristic of the 2D WS 2 material, the pulsed Nd:Gd 0.89 La 0.1 NbO 4 laser performance was investigated. The shortest pulse duration of 895 ns and the highest repetition rate of 162 kHz were realized at an absorbed pump power of 7.18 W. [ABSTRACT FROM AUTHOR]