Revealing switchable pulse dynamics in an all-fiber Mamyshev oscillator

Ultrafast fiber lasers based on the passive mode-locking mechanism can sustain various single- or multiple-pulse dynamic phenomena. The Mamyshev oscillator (MO) demonstrates significant potential for generating high-performance optical pulses. However, investigations into pulse-switching dynamics in oscillators have received scant attention, particularly in chaotic pulsing regimes. In this work, we implement an all-fiber MO laser system based on erbium-doped fiber and experimentally observe novel switchable pulse dynamics, to our knowledge. Stable single- and multiple-pulse mode-locking operation regimes are achieved by modulating the pump power and the polarization state. The number of pulses within the multiple-pulse bunch tends to increase linearly with the pump power, with an average time interval between 0.49 and 0.76 ns. Furthermore, the chaotic pulse regime is also observed at an elevating pump power. These results can facilitate the understanding of nonlinear pulse dynamics in ultrafast fiber lasers.