Pulsating synchronized trichromatic pulse compound based on four-wave mixing effect in a passively mode-locked fiber laser

The formation of synchronized multi-wavelength pulses in mode-locked lasers is crucial for exploring multi-dimensional soliton dynamics. However, in traditional multi-wavelength mode-locked lasers, pulses of different wavelengths often experience group velocity differences due to dispersion, making synchronization challenging. In this work, we demonstrate that trichromatic pulses can be synchronized within the fiber laser cavity through four-wave mixing (FWM)-induced energy exchange by using a section of zero-dispersion fiber. The resulting synchronized trichromatic pulse compound (STPC) with noisy properties also exhibits pulsating dynamics, where the trichromatic pulses share the same pulsation period. Moreover, asynchronous pulses generated during the energy dissipation processes of the STPC also follow the same pulsation period. Moreover, these pulsating asynchronous pulses, functioning as a self-organizing process, regulate the stability of the pulsating STPC in different ways under different pump powers. This work provides a promising method for studying the dynamics of multi-dimensional dissipative solitons and is expected to promote the related applications of synchronized multi-wavelength mode-locked fiber lasers.