Purcell-Enhanced Emission from Individual SiV${}^{-}$ Center in Nanodiamonds Coupled to a Si${}_3$N${}_4$-Based, Photonic Crystal Cavity

Abstract

Hybrid quantum photonics combines classical photonics with quantum emitters in a postprocessing step. It facilitates to link ideal quantum light sources to optimized photonic platforms. Optical cavities enable to harness the Purcell-effect boosting the device efficiency. Here, we postprocess a free-standing, crossed-waveguide photonic crystal cavity based on Si${}_3$N${}_4$ with SiV${}^{-}$ center in nanodiamonds. We develop a routine that holds the capability to optimize all degrees of freedom of the evanescent coupling term utilizing AFM nanomanipulation. After a few optimization cycles we resolve the fine-structure of individual SiV${}^{-}$ centers and achieve a Purcell enhancement of more than 4 on individual optical transitions, meaning that four out of five spontaneously emitted photons are channeled into the photonic device. Our work opens up new avenues to construct efficient quantum photonic devices.

7 pages, 4 figures. Nanophotonics (2020)