Tunable optical frequency comb generation in a periodically poled lithium niobate waveguide based on stimulated Brillouin scattering

We propose and demonstrate a technique for the generation of an optical frequency comb (OFC) in a periodically poled lithium niobate (PPLN) waveguide based on stimulated Brillouin scattering. A single continuous wave laser is sent to a multi-wavelength Brillouin erbium fibre laser for generating a set of coherent and phase-locked multi-wavelength spectral lines. They are injected into a PPLN waveguide to obtain an OFC. We investigate the influence of the cavity structure on the OFC property in our two different schemes. The number of comb lines is affected by the 980 pump current and Brillouin pump power. The OFCs are tunable in a large range by changing their central wavelength.