On‐Chip Apodized Hybrid Photonic‐Plasmonic Cavity QED for Polarized Single Photons Coupling

Abstract A system is proposed for the efficient coupling of plasmon‐enhanced polarized single photons into a 1D apodized hybrid photonic‐plasmonic (HPP) cavity structure, to realize cavity quantum electrodynamics (QED). The HPP cavity is formed by placing a gold nanorod (GNR) on an apodized 1D photonic crystal (PhC) cavity designed on a diamond waveguide. It is shown that the spontaneous emission of quantum emitters (QE) can be strongly enhanced by utilizing the combination of GNR and Phc cavity structure, leading to the emission of highly polarized and bright single photons. The Purcell factor is numerically estimated as high ≈5303, with a cavity‐enhanced coupling efficiency of up to ≈24.3% and a degree of polarization (DOP) of more than 99%, in the guided modes of the HPP cavity. Under the resonance condition, a 28‐fold increase in enhancement factor in the HPP cavity as compared to a moderate finesse‐based Phc cavity is achieved. The cavity is designed to minimize the losses, resulting in a scattering‐limited Q ‐factor and one‐pass loss estimated to be around 21500 and 0.1%, respectively. This work paves the way to realize quantum photonic devices based on efficient photonic interfaces for on‐chip quantum information processing applications.