Passively Q-switched operation based on Sb2Se3 and self-power near infrared photodetector

In this paper, Antimony selenide （Sb2Se3） nanorods are prepared by the hot solvent method, the Sb2Se3 is detected by near-infrared detectors with good photoelectric properties. Afterwards its nonlinear optical performance was tested, compared with metal chalcogen compounds, the prepared Sb2Se3 has great bandwidth saturation absorption response, higher modulation depth (43.27%) and lower saturation intensity (2.13 MW/cm2), which is very suitable for making saturable absorber (SA) devices. In addition, we integrate Sb2Se3 SA into a 1.5 μm erbium-doped fiber laser and realize Q-switching for the first time. Our results show the obtained Q-switched laser has high single pulse energy and low self-starting threshold and good stability. Moreover, by adjusting the polarization state, a stable double wavelength spectrum appears. This indicates that Sb2Se3 has outstanding application potential in optical switching devices and pulse laser engineering. •Sb2Se3 SA have excellent photoelectric performance，large modulation depth (43.27%) and low saturation (2.13 MW/cm2) intensity.•We selected the 808nm self-power photodetector with better light absorption of Sb2Se3 and showed the Sb2Se3 optical switch behavior is very stable.•Based on the Sb2Se3 SA, we obtained stable single-wavelength and dual-wavelength Q-switching pulses for the first time. And better single pulse energy of 302nJ is achieved.