Four-wave-mixing-assisted Brillouin fiber laser with double-Brillouin-frequency spacing

• Brillouin fiber laser with 18 channels at 0.176 nm spacing is presented.
• Bandpass filter suppressed the ASE noise floor producing higher OSNR at the output.
• The incorporation of bandpass filter increases number of channels from 15 to 18.

The generation of multiwavelength Brillouin fiber laser assisted by four wave mixing has been demonstrated. A maximum of 18 channels of laser Stokes lines are generated at a Brillouin Pump (BP) of 190 mW (∼22.5 dBm). The multiple peaks have a wavelength spacing of 0.176 nm (∼20 GHz). A tunable optical bandpass filter is incorporated to the design to suppress up to 6 dB of the noise floor hump exhibited at the multiwavelength laser spectrum while limiting the laser peaks attenuation thereby providing a much cleaner and better OSNR.