Long-time stable Q-switched bulk laser at 1.34 and 1.94 μm based on antimonene saturable absorber

The low stability of laser pulse production induced by the deterioration of saturable absorber (SA) under long-time laser excitation is a common shortage of passive Q-switched bulk lasers that strongly impedes their general applications. The 2D mono-elemental nanomaterial antimonene has been recently verified as a promising SA for realizing high-stability pulsed fiber laser benefiting from its stable semimetallic bonding and superior thermal conductivity. However, its performance in enhancing the stability of pulsed bulk laser has less been investigated. Here we demonstrated the successful application of multi-layer antimonene for stable passive Q-switching operations in Tm:YAP laser at 1.94 μm and Nd:GdVO4 laser at 1.34 μm. The multi-layer antimonene was characterized to have broadband SA properties with a modulation depth of 3.2 % (12.2 %) and a saturable intensity of 0.19 GW/cm2 (0.17 GW/cm2) at 1.94 μm (1.34 μm). Stable Q-switched pulses were obtained with pulse duration of 238 ns at 1.94 μm and 324 ns at 1.34 μm. The long-time pulse duration instability was only 9.6 % at 1.94 μm and 6.9 % at 1.34 μm within 180-minute measurement. Our work indicates the exceptional potential of antimonene SA in infrared pulsed bulk laser, which may arouse great interest for developing antimonene-based optics and optoelectronics applications with enhanced stability.