A pump power controlled multiwavelength fiber laser with adjustable output channels at fixed wavelength

We report an experimental demonstration of multiwavelength erbium-doped fiber laser with adjustable wavelength number exploiting a power-symmetric nonlinear optical loop mirror (NOLM). As the pump power increases from 53 mW to 410 mW, one-seven lasing line(s) at fixed wavelength around 1571 nm are obtained. A theoretical model describing the NOLM and the EDF is established to investigate the effect of the pump power on the lasing characteristics. Numerical results confirm the experiment measurements and indicate that it is the intensity-dependent loss of lasing beams generated in the NOLM that leads to such phenomena.