Two-dimensional tin diselenide as the saturable absorber for passively Q-switched Er:YAP 3 μm solid-state laser

Abstract

A passively Q-switched (PQS) Er:YAP laser at ∼3 μm with the two-dimensional saturable absorber (SA) tin diselenide (SnSe2) nanosheet as SA was successfully demonstrated for the first time. Under the maximum absorbed pump power of 4.0 W, the obtained continuous-wave maximum output power of Er:YAP laser was 258 mW with a corresponding slop efficiency of 7.18%. In the PQS experiment, laser pulses with the shortest pulse duration of 198 ns were yielded with a repetition rate of 317 kHz under the maximum absorbed pump power of 4.0 W, and the corresponding single pulse energy and pulse peak power were 0.66 µJ and 3.3 W, respectively. The investigation indicates that SnSe2 has the potential to be an outstanding laser modulator for PQS solid-state laser at 3 μm wavelength.