Polarization modulation instability in a nonlinear fiber Kerr resonator.

We report on the experimental and numerical observation of polarization modulation instability (PMI) in a nonlinear fiber Kerr resonator. This phenomenon is phased-matched through the relative phase detuning between the intracavity fields associated with the two principal polarization modes of the cavity. Our experimental investigation is based on a 12 m long fiber ring resonator in which a polarization controller is inserted to finely control the level of intracavity birefringence. Depending on the amount of birefringence, the temporal patterns generated via PMI are found to be either stationary or to exhibit a period-doubled dynamics. The experimental results are in good agreement with numerical simulations based on an Ikeda map for the two orthogonally polarized modes. This Letter provides new insights into the control of modulation instability in multimode Kerr resonators.