Dual-wavelength Soliton Dumbbell-shaped Thulium-doped Fiber Laser

Dual-wavelength ultra-short pulses generation in the dumbbell-shaped thulium fiber laser was demonstrated. The mode-locking regime was achieved by using single-walled carbon nanotubes in the laser cavity. Output power was up to 6 mW and the main repetition rate was around 5.3 MHz.