978 nm dispersion-managed soliton generation from an all-polarization-maintaining Yb-doped figure-of-9 fiber laser

Restricted by the narrow gain bandwidth of Yb3+ near 980 nm, it is challenging to generate dispersion-managed (DM) solitons at this wavelength. In this work, we demonstrate the generation of DM solitons at 978 nm in an all-polarization-maintaining (PM) figure-of-9 fiber laser. Highly coherent pulses with 14.4 nm spectral bandwidth and 175 fs pulse duration are experimentally obtained. To the best of our knowledge, it is the shortest ~980 nm pulse ever reported in an Yb-doped mode-locked fiber laser. Numerical simulations are performed to reveal the DM solitons’ temporal and spectral evolution inside the figure-of-9 cavity under the condition of narrow gain bandwidth. This robust and cost-effective 978 nm femtosecond laser is a promising light source for applications such as underwater communication and biophotonics.