Wide-range optical carrier recovery via broadened Brillouin filters

Stimulated Brillouin scattering has great potential for wide-wavelength-range optical carrier recovery, as it can act as a parametrically defined narrowband gain filter. However, due to the dispersion of the Brillouin frequency shift, prior demonstrations have been limited in wavelength range. Here, we demonstrate that frequency modulating the pump light for a gain filter based on stimulated Brillouin scattering enables optical carrier recovery for a broad range of input wavelengths. We demonstrate highly selective (<150M H z bandwidth) amplification for optical carriers over an 18 nm wide wavelength range in the optical communications C-band, an ∼6× improvement over using an unmodulated pump. Measurements of the noise properties of these spectrally broadened gain filters, in both amplitude and phase, indicate the noise performance and SNR are maintained over a wide wavelength range. Our technique provides a potential solution for highly selective, wavelength agnostic optical carrier recovery.