A 2 micron passively Q-switched bulk state pulsed laser based on WS2

Abstract

We report a 2 micron passively Q-switched bulk state pulsed laser with a pulse of 430 ns based on graphene-like 2D WS₂ nanosheets. To the best of our knowledge, it is the shortest pulse compared with other bulk state lasers based on WS₂ saturable absorbers at this waveband. The WS₂ nanosheets are prepared through a facile hydrothermal reaction. Its max output power and pulse energy are 488 mW and 5.422 μJ, respectively. The wavelength is distributed from 1934 to 1942 nm. These results reveal that WS₂ is a promising nanomaterial in the fields of photonics and electronics.