Metal-Dielectric Antennas for Efficient Photon Collection from Diamond Color Centers

TL;DR

This paper presents optimized metal-dielectric nanoantenna designs embedded in diamond that significantly enhance photon collection efficiency from nitrogen vacancy centers, enabling improved quantum measurements at room temperature.

Contribution

Introduction of novel metal-dielectric nanoantenna structures aligned with quantum emitters to boost photon collection from diamond NV centers.

Findings

Over two orders of magnitude increase in photon collection rate.

Optimized antenna design balances efficiency, Purcell factor, and emission directionality.

Potential for single-shot spin measurements at room temperature.

Abstract

A central challenge in quantum technologies based on atom-like defects is the efficient collection of the emitter's fluorescence. Optical antennas are appealing as they offer directional emission together with spontaneous emission rate enhancement across a broad emitter spectrum. In this work, we introduce and optimize metal-dielectric nanoantenna designs recessed into a diamond substrate and aligned with quantum emitters. We analyze trade-offs between external quantum efficiency, collection efficiency, Purcell factor, and overall collected photon rate. This analysis shows that an optimized metal-dielectric hybrid structure can increase the collected photon rate from a nitrogen vacancy center by over two orders of magnitude compared to a bare emitter. As a result, these metal-dielectric antennas should enable single-shot electron spin measurements of NV centers at room temperature.