Deterministic nano-assembly of a coupled quantum emitter - photonic crystal cavity system

TL;DR

This paper demonstrates a precise method for coupling single quantum emitters, specifically NV centers, to photonic crystal cavities, significantly enhancing emission and enabling advanced quantum photonic applications.

Contribution

It introduces a deterministic positioning technique for NV centers in gallium phosphide photonic crystal cavities with nanometer accuracy.

Findings

25-fold enhancement of NV emission at cavity wavelength

Reshaping of NV photoluminescence spectrum

Potential for efficient coherent photon generation

Abstract

The interaction of a single quantum emitter with its environment is a central theme in quantum optics. When placed in highly confined optical fields, such as those created in optical cavities or plasmonic structures, the optical properties of the emitter can change drastically. In particular, photonic crystal (PC) cavities show high quality factors combined with an extremely small mode volume. Efficiently coupling a single quantum emitter to a PC cavity is challenging because of the required positioning accuracy. Here, we demonstrate deterministic coupling of single Nitrogen-Vacancy (NV) centers to high-quality gallium phosphide PC cavities, by deterministically positioning their 50 nm-sized host nanocrystals into the cavity mode maximum with few-nanometer accuracy. The coupling results in a 25-fold enhancement of NV center emission at the cavity wavelength. With this technique, the NV center photoluminescence spectrum can be reshaped allowing for efficient generation of coherent photons, providing new opportunities for quantum science.