Spontaneous emission and collection efficiency enhancement of single emitters in diamond via plasmonic cavities and gratings

TL;DR

This paper presents a plasmonic cavity and grating approach to enhance the spontaneous emission rate and collection efficiency of single NV centers in diamond, addressing photon loss issues.

Contribution

It introduces a novel plasmonic cavity with gratings that simultaneously boosts emission rate and collection efficiency of single emitters in diamond.

Findings

Enhanced spontaneous emission rate of NV centers.

Improved photon collection efficiency.

Reduced photon losses into surface plasmons and reflections.

Abstract

We demonstrate an approach, based on plasmonic apertures and gratings, to enhance the radiative decay rate of single NV centers in diamond, while simultaneously improving their collection efficiency. Our structures are based on metallic resonators formed by surrounding sub-wavelength diamond nanoposts with a silver film, which can enhance the spontaneous emission rate of an embedded NV center. However, the collection efficiency of emitted photons remains low due to losses to surface plasmons and reflections at the diamond-air interface. In this work, we mitigate photon losses into these channels by incorporating grating structures into the plasmonic cavity system.