We report the design, fabrication, and characterization of a photonic crystal microresonator exhibiting a constant free spectral range. More than 50 resonances with Q > 2 × 105 are observed in a 200 μm long and 650 nm wide III–V semiconductor cavity heterogeneously integrated on a silicon photonic circuit (Silicon on Insulator). We measured stimulated four wave mixing with a −12 dB signal to idler conversion. Two photon absorption is prevented owing to the wide electronic bandgap of the III–V semiconductor (indium gallium phosphide) enabling the possibility to use sufficiently large optical power densities for efficient nonlinear parametric interactions.
