Well-aligned single-walled carbon nanotubes for optical pulse generation and laser operation states manipulation

We report operation switchable fiber lasers by using well-aligned (2,2) single-walled carbon nanotubes (SWCNTs) as saturable absorber. These SWCNTs are fabricated in the elliptical nanochannels of ZnAPO4-11(AEL) zeolite single crystal, which features anisotropic optical absorption. Thus, these SWCNTs can act as an excellent polarization sensitive saturable absorber for the wide-band optical pulse generation and laser operation states manipulation. By putting a SWCNTs@AEL single crystal into erbium-, and ytterbium-doped fiber laser cavities, stable mode-locking and Q-switching pulses can be switched by simply adjusting a polarization controller under a fixed pump power, respectively.