Three megahertz photon collection rate from an NV center with millisecond spin coherence

TL;DR

This paper demonstrates a diamond-based photonic structure that significantly enhances photon collection rates from a single NV center while maintaining a long spin coherence time, advancing quantum sensing and information applications.

Contribution

Introduction of a circular bullseye diamond grating that boosts photon collection rate from NV centers without compromising their spin coherence.

Findings

Photon collection rate of approximately 3 million counts per second.

Spin coherence time of about 1.7 milliseconds.

Efficient redistribution of emitted photons into low-NA modes.

Abstract

Efficient collection of the broadband fluorescence of the diamond nitrogen vacancy center is essential for a range of applications in sensing, on-demand single photon generation, and quantum information processing. Here, we introduce a circular `bullseye' diamond grating enabling a collected photon rate of $(3.0\pm0.1)\times10^6$ counts per second from a single nitrogen-vacancy center with a spin coherence time of 1.7$\pm$0.1 ms. Back-focal-plane studies indicate efficient redistribution into low-NA modes.