Self-oscillating frequency comb generation with a stimulated Brillouin scattering based optoelectronic oscillator

A self-oscillating optical frequency comb (OFC) generator based on an electrical filter-free optoelectronic oscillator (OEO) is proposed and experimental demonstrated. By using stimulated Brillouin scattering (SBS) in a fiber, phase-modulation to intensity-modulation conversion is achieved to realize an oscillation in a loop. The generated oscillation signal has a frequency equal to a Brillouin frequency shift in the fiber, and it is used to drive another phase modulator to generate OFC lines. A 9-tone frequency comb is demonstrated with a power variation of 3 dB, and the single-sideband phase noise of the OEO is measured to be −80 dBc/Hz at 10 kHz offset frequency.