Multi-wavelength erbium-doped fiber laser based on random distributed feedback

We experimentally demonstrated a multi-wavelength erbium-doped fiber laser based on random distributed feedback via a 20-km-long single-mode fiber together with a Sagnac loop mirror. The number of channels can be modulated from 2 to 8 at room temperature when the pump power is changed from 30 to 180 mW, indicating that wavelength competition caused by homogenous gain broadening of erbium-doped fiber is significantly suppressed. Other advantages of the laser include low cost, low-threshold pump power and simple fabrication.