Dielectric Fano Nanoantennas for Enabling Sub‐Nanosecond Lifetimes in NV‐Based Single Photon Emitters

Abstract Solid‐state quantum emitters are essential sources of single photons, and enhancing their emission rates is of paramount importance for applications in quantum communications, computing, and metrology. One approach is to couple quantum emitters with resonant photonic nanostructures, where the emission rate is enhanced due to the Purcell effect. Dielectric nanoantennas are promising as they provide strong emission enhancement compared to plasmonic ones, which suffer from high Ohmic loss. Here, a dielectric Fano resonator is designed and fabricated based on a pair of silicon (Si) ellipses and a disk, which supports the mode hybridization between quasi‐bound‐states‐in‐the‐continuum (quasi‐BIC) and Mie resonance. The performance of the developed resonant system is demonstrated by interfacing it with single photon emitters (SPEs) based on nitrogen‐vacancy (NV) centers in nanodiamonds (NDs). It is observed that the interfaced emitters have a Purcell enhancement factor of ≈10, with sub‐ns emission lifetime and a polarization contrast of 9. The results indicate a promising method for developing efficient and compact single‐photon sources for integrated quantum photonics applications.