Comprehensive analysis of pure-quartic soliton dynamics in a passively mode-locked fiber laser

Abstract

The understanding of soliton dynamics promotes the development of ultrafast laser technology. High-energy pure-quartic solitons (PQSs) have gradually become a hotspot in recent years. Herein, we numerically study the influence of gain bandwidth, saturation power, small-signal gain, and output coupler on PQSs dynamic in passively mode-locked fiber lasers. The results present that the above four parameters can affect PQS dynamics. Pulsating PQSs occur as alter other three parameters when taken gain bandwidth as 50 nm. Meanwhile, PQSs show an evolution from pulsating to erupting and then to splitting as altered other three parameters when taken gain bandwidth as 10 nm, which can be attributed to the existence of spectral filtering effect and intra-cavity fourth-order dispersion. These findings provide new insights into PQSs dynamics in passively mode-locked fiber lasers.