Passively Q-switched Er-doped fiber laser based on NbSe2 quantum dot saturable absorber

In this work, an all-fiber passively Q-switched Er-doped fiber laser(EDFL) is firstly demonstrated by using NbSe2 quantum dot as a saturable absorber(SA), to the best of our knowledge. A stable passively Q-switched laser at 1533 nm is achieved at a threshold pump power of 42 mW by inserting the NbSe2-SA into the EDFL cavity. By increasing gradually the pump power from 42 to 192 mW, the pulse duration decreases from 5.12 to 2.53 μs and the single pulse energy increase from 35.07 to 98.19 nJ. The results indicate that NbSe2 quantum dot has excellent saturable absorption properties, which will have wide potential applications in the field of pulse lasers.