Passively Q-switched mode-locked fiber laser with 1-GHz fundamental repetition rate based on zeolite-fabricated Yb-Mg-doped silica glass

We successfully demonstrated a pulse laser with a fundamental repetition rate of 1 GHz in passively Q -switched mode-locked oscillation by using Yb-Mg-doped silica glass fiber (YbMgSGF). The YbMgSGF core glass, fabricated by the zeolite method, showed a Yb2O3 content of 5.46 wt%. To the best of our knowledge, our laser is the first silica-glass-based, Yb-doped fiber laser operating at a fundamental repetition rate of gigahertz. The laser cavity was constructed by a 102-mm-long YbMgSGF as a laser medium and a semiconductor saturable -absorber mirror as a mode-locker. The laser output power reached 5.93 mW, and its slope efficiency and lasing threshold power were 3.6% and 5.3 mW, respectively. The peak wavelength of the oscillation was 1039 nm. We also discuss the conditions to transition from Q-switched mode-locked operation to continuous-wave mode -locked operation. The proposed fiber laser can serve as a seed laser for a master oscillator power amplifier for a high-power, high-efficiency pulsed fiber laser source.

Automated summary

We demonstrated a pulse laser with a fundamental repetition rate of 1 GHz using Yb-Mg-doped silica glass fiber. The laser cavity consisted of a 102-mm-long YbMgSGF as the laser medium and a semiconductor saturable-absorber mirror as a mode-locker. The laser output power reached 5.93 mW with a slope efficiency of 3.6% and a lasing threshold power of 5.3 mW.