Deterministic integration of single nitrogen-vacancy centers into nanopatch antennas

TL;DR

This paper presents a deterministic method for integrating single nitrogen-vacancy centers into plasmonic nanoantennas, enabling controlled coupling and enhanced quantum emission for quantum information and sensing applications.

Contribution

A novel deterministic transfer and coupling technique for single NV centers into nanoantennas with precise geometry control.

Findings

Significant reduction in NV fluorescence lifetime due to nanoantenna coupling

Ability to measure coherent spin dynamics in coupled NV-nanoantenna system

Enhanced quantum emission suitable for quantum information applications

Abstract

Quantum emitters coupled to plasmonic nanoantennas produce single photons at unprecedentedly high rates in ambient conditions. This enhancement of quantum emitters' radiation rate is based on the existence of optical modes with highly sub-diffraction volumes supported by plasmonic gap nanoantennas. Nanoantennas with gap sizes on the order of few nanometers have been typically produced using various self-assembly or random assembly techniques. Yet, the difficulty of controllably fabricate nanoantennas with the smallest mode sizes coupled to pre-characterized single emitters until now has remained a serious issue plaguing the development of quantum plasmonic devices. We demonstrate the transfer of nanodiamonds with single nitrogen-vacancy (NV) centers to an epitaxial silver substrate and their subsequent deterministic coupling to plasmonic gap nanoantennas. Through fine control of the assembled nanoantenna geometry, a dramatic shortening of the NV fluorescence lifetime was achieved. We furthermore show that by preselecting NV centers exhibiting a photostable spin contrast, a coherent spin dynamics can be measured in the coupled configuration. The demonstrated approach opens unique applications of plasmon-enhanced quantum emitters for integrated quantum information and sensing devices.