Observation of pulsating dissipative solitons in a Mamyshev oscillator
Bo Cao, Kangjun Zhao, Chenxin Gao, Xiaosheng Xiao, Chengying Bao, Changxi Yang
Abstract
Dissipative solitons (DSs) widely exist in optical systems and mode-locked fiber lasers provide a versatile playground to study their dynamics. Recently, Mamyshev oscillators (MOs), which rely upon a pair of narrow filters with offset passing frequencies, have emerged as a new type of femtosecond fiber lasers. Besides creating high-energy broadband DSs, MOs have been predicted to support periodically pulsating DSs whose observation remains elusive. Here, we present a comprehensive experimental and numerical investigation of pulsating DSs in an ytterbium MO. By reducing the filter separation, we observe pulsation in both single-pulse and DS molecule states. The output pulse energy can vary as large as 40 times in our MO. Single-shot spectra measured by the dispersive Fourier transform method further enables the observation of spectral bandwidth breathing and soliton explosion in the pulsation. In addition, pulsation lasting 9 round trips and even a chaotic pulsation state are observed. Numerical simulations based on a lumped vector model qualitatively agree with our observation. Our results enrich pulsating DS dynamics and reveal the impact of filter separation on the stability of MOs.