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arXiv · 2402.13557

Nano antenna-assisted quantum dots emission into high-index planar waveguide

X. Yu·J. -C. Weeber·L. Markey·J. Arocas·A. Bouhelier·A. Leray·G. Colas des Francs
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Abstract

Integrated quantum photonic circuits require the efficient coupling of photon sources to photonic waveguides. Hybrid plasmonic/photonic platforms are a promising approach, taking advantage of both plasmon modal confinement for efficient coupling to a nearby emitter and photonic circuitry for optical data transfer and processing. In this work, we established directional quantum dot (QD) emission coupling to a planar TiO$_2$ waveguide assisted by a Yagi-Uda antenna. Antenna on waveguide is first designed by scaling radio frequency dimensions to nano-optics, taking into account the hybrid plasmonic/photonic platform. Design is then optimized by full numerical simulations. We fabricate the antenna on a TiO$_2$ planar waveguide and deposit a few QDs close to the Yagi-Uda antenna. The optical characterization shows clear directional coupling originating from antenna effect. We estimate the coupling efficiency and directivity of the light emitted into the waveguide.

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X. Yu, J. -C. Weeber, L. Markey, J. Arocas, A. Bouhelier, A. Leray, G. Colas des Francs. 2024-02-21. Nano antenna-assisted quantum dots emission into high-index planar waveguide. https://arxiv.org/abs/2402.13557

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