Passively Q-switched pulses generation from Erbium-doped fiber laser based on microfiber coated PbS quantum dots

Passively Q-switched pulses generation from Erbium-doped fiber laser based on PbS quantum dots (QDs) with microfiber as saturable absorber (SA) is demonstrated in this work. We successfully fabricate the microfiber with the diameter of ∼5.86 μm and the PbS QDs with an obvious absorption at 1550 nm. The passively Q-switched operation is realized using the interaction between the QDs and the evanescent field. The maximum output power of 14.9 mW and maximum single pulse energy of 121.2 nJ are realized at the pump power of 457 mW. To the best of our knowledge, this is the first demonstration of passively Q-switched generation using PbS QDs on microfiber as SA.