Comb of high‐Q Resonances in a Compact Photonic Cavity

The optical equivalent of the quantum mechanical oscillator is demonstrated in a photonic crystal cavity, owing to the balance of the background dispersion and a bichromatic potential. Consequently, several equi‐spaced resonances with large loaded Q factors are obtained within a very tiny volume. A detailed statistical analysis is carried out by exploiting the complex reflection spectra measured with Optical Coherent Tomography. The log‐normal distribution of the intrinsic Q‐factors is centered at 0.7 million. The device is made of Ga0.5In0.5P in order to suppress the two photon absorption in the Telecom spectral range considered here. This is crucial to turn the strong localization of light into ultra‐efficient parametric interactions. The photonic equivalent of the quantum mechanical harmonic oscillator is implemented in a ≈25μm long nanopatterned resonator. A comb of equispaced resonances is revealed by a detailed statistical experimental analysis. The normally distributed fluctuations are small enough to allow ultra efficient nonlinear interaction involving many modes, owing to the their very large quality factors and very tiny volume.