Utilizing black phosphorus as a Q-switcher in Nd-doped fiber laser system

We successfully develop a pulsed fiber laser, operating at 1088 nm, by utilizing a neodymium-doped fiber (NDF) as the gain medium and black phosphorus (BP) material as a saturable absorber (SA). We construct the SA by transferring multilayer BP material onto a fiber ferrule tip via mechanical exfoliation, subsequently integrated into an NDFL ring cavity to modulate the cavity loss and generate Q-switched pulses. Notably, as the 808 nm pumping power increases from 44.7 to 90.6 mW, the laser’s output pulse duration decreased from 15.1 to 10.6 µs, while the repetition rate increases from 21.93 to 42.92 kHz. Demonstrating stable pulse train output, the laser exhibits a fundamental frequency with a signal to background noise ratio of 35 dB. This pioneering work represents the first report to employ BP as SA within an NDFL cavity.