Analysis of all-optical intra-cavity wavelength conversions in fiber ring resonators

The cascaded second-order nonlinear interaction (χ(2)) based wavelength conversions using fiber ring resonator schemes were studied both theoretically and experimentally. The schemes contain erbium doped fiber amplifiers (EDFAs), optical circulators and fiber Bragg gratings exclusively as a pump source, with excellent characteristics such as high black-box conversion efficiency and strong pump light confinement. It is shown that a maximum black-box conversion efficiency of −10 dB can be obtained by using an EDFA with a saturation power of only 16 dBm and a quasiphase matched waveguide with a nonlinear conversion efficiency of 280%/W. The standard and black-box conversion efficiencies, and ring structure design were also investigated and compared theoretically based on three kinds of ring resonator configurations. The analysis provides a guideline for optimizing wavelength conversion efficiency based on the proposed ring resonators.