Beaming light from a quantum emitter with a planar optical antenna

TL;DR

This paper introduces a simple, broadband planar optical antenna that efficiently beams light from a single quantum emitter, enhancing collection without complex positioning or optics, suitable for various quantum photonics applications.

Contribution

The paper presents a novel, easy-to-fabricate planar optical antenna that improves photon collection from quantum emitters without stringent emitter positioning.

Findings

Increased collection efficiency at small angles

Broadband and spectrally scalable performance

Applicable to various quantum emitters

Abstract

The efficient interaction of light with quantum emitters is crucial to most applications in nano and quantum photonics, such as sensing or quantum information processing. Effective excitation and photon extraction are particularly important for the weak signals emitted by a single atom or molecule. Recent works have introduced novel collection strategies, which demonstrate that large efficiencies can be achieved by either planar dielectric antennas combined with high numerical-aperture objectives or optical nanostructures that beam emission into a narrow angular distribution. However, the first approach requires the use of elaborate collection optics, while the latter is based on accurate positioning of the quantum emitter near complex nanoscale architectures; hence, sophisticated fabrication and experimental capabilities are needed. Here, we present a theoretical and experimental demonstration of a planar optical antenna that beams light emitted by a single molecule, which results in increased collection efficiency at small angles without stringent requirements on the emitter position. The proposed device exhibits broadband performance and is spectrally scalable, and it is simple to fabricate and therefore applies to a wide range of quantum emitters. Our design finds immediate application in spectroscopy, quantum optics and sensing.