Switchable and dual-wavelength ultrafast fibre lasers with an MoTe2-based saturable absorber

Based on monolayer MoTe2 film, we have proposed a mode-locked fibre laser delivering single-wavelength and dual-wavelength solitons at the telecommunication band. The saturable absorber (SA) is synthesized by coating monolayer MoTe2 film on the pinhole of fibre pigtail. The experimental results show that our soliton lasers can work at the single- and dual-wavelength states, respectively, by appropriately adjusting the polarization controller. The proposed laser can work stably at the mode-locking state for several hours, indicating that monolayer MoTe2 film is an excellent SA material for ultrafast optics.