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

TL;DR

This paper demonstrates Purcell-enhanced emission from individual SiV$^-$ centers in nanodiamonds coupled to a Si$_3$N$_4$ photonic crystal cavity, achieving over fourfold emission enhancement and enabling efficient quantum photonic device construction.

Contribution

It introduces a routine for optimizing evanescent coupling via AFM nanomanipulation and resolves fine-structure of SiV$^-$ centers, advancing hybrid quantum photonics.

Findings

Achieved Purcell enhancement of over 4 times for individual SiV$^-$ centers.

Developed a routine for optimizing evanescent coupling using AFM nanomanipulation.

Resolved the fine-structure of individual SiV$^-$ centers in nanodiamonds.

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.