A metal-dielectric parabolic antenna to direct single photons

TL;DR

This paper introduces a 3D metal-dielectric parabolic antenna that efficiently directs single photons from quantum dots, enhancing collection and manipulation for quantum technologies with high directivity and broad spectral range.

Contribution

The work presents a novel fabrication method for a robust, broadband parabolic antenna that significantly improves photon collection efficiency and directivity compared to traditional nano-antennas.

Findings

Achieved a directivity of D=106 and beam divergence of 13.5 degrees.

Demonstrated over 96% photon extraction efficiency.

Operates effectively across visible and near-IR spectrum.

Abstract

Quantum emitters radiate light omni-directionally, making it hard to collect and use the generated photons. Here we propose a 3D metal-dielectric parabolic antenna surrounding an individual quantum dot as a source of collimated single photons which can then be easily extracted and manipulated. Our fabrication method relies on a single optically-induced polymerization step, once the selected emitter has been localized by confocal microscopy. Compared to conventional nano-antennas, our geometry does not require near-field coupling and it is therefore very robust against misalignment issues, and minimally affected by absorption in the metal. The parabolic antenna provides one of the largest reported experimental directivities (D=106) and the lowest beam divergences ({\Theta}=13.5 deg), a broadband operation over all the visible and near-IR range, together with more than 96% extraction efficiency, offering a practical advantage for quantum technological applications.