Optical Scattering Induced Noise in Fiber Ring Resonators and Optoelectronic Oscillators

This paper reports both theoretical and experimental studies on nonlinear optical phenomena generated at very low thresholds in fiber ring resonators featuring ultrahigh quality factors. These studies are focused on two optical scattering phenomena: the Rayleigh and the Brillouin scatterings. The effects of these scattering phenomena on the phase noise of an optoelectronic oscillator based on the fiber ring resonator are detailed. A 30 dB reduction in the oscillator phase noise at 10 Hz offset frequency has been demonstrated by limiting the nonlinear scattering effects when using low input optical power. Moreover, a new high quality factor fiber ring resonator, optimized and immunized against some of these nonlinear optical effects, has been designed and an oscillator phase noise level of -50 dBc/Hz at 10 Hz offset frequency has been achieved.