L-band passively mode-locked fiber laser based on WS2 saturable absorber

We demonstrate a compact erbium-doped fiber ring laser mode-locked by a WS
₂
saturable absorber (SA), which operates in the telecommunication L-band. The monolayer WS
₂
is synthesized by an enhanced chemical vapor deposition (CVD) method and transferred onto the end face of a fiber connector to form a fiber-compatible WS
₂
SA. Stable soliton pulses centered at 1602.2 nm with a pulse duration of 1.19 ps are achieved in the laser. Our research results show that monolayer WS
₂
is a promising material for L-band ultrashort pulse generation.