WS2/fluorine mica (FM) saturable absorber for high power optical pulse formation

The report presents the high power mode-locking operation in an anomalous-dispersion fiber laser with a novel WS2 saturable absorber (SA) based on fluorine mica (FM) substrate. Compared to organic host material such as polymer, FM has higher softening temperature, heat dissipation and laser damage threshold. By employing the SA, a stable mode-locked fiber laser is achieved. The duration of the pulse broadens from 2.816 ns to 3.654 ns almost linearly with increasing pump power. The average output power and single pulse energy can increase up to 33.5 mW and 4 nJ at the maximum pump power respectively. The results indicate that WS2/FM material is an ideal SA for high power Er-doped fiber (EDF) lasers.