Graphene and nanotube mode-locked fiber laser emitting dissipative and conventional solitons.

We propose a bidirectional erbium-doped fiber laser mode-locked with a mixture of graphene and single-walled carbon nanotubes for the first time to our best knowledge. The fiber laser can deliver dissipative soliton (DS) and conventional soliton (CS), circulating in opposite directions. The net-cavity dispersion is normal in the clockwise direction and anomalous in counter clockwise direction, respectively, and then DS and CS are generated with the suitable adjustment of attenuators. The output DS and CS approximately have the same central wavelength, but exhibit different optical spectra, pulse durations, and repetition rates. The all-fiber switchable laser can provide two different pulse sources, which is convenient for practical applications.