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arXiv · 2508.06223

Aspheric lens design proposal for near-perfect mode-matching of a broadband quantum dot micropillar to a single-mode fibre

Yichen Zhang·David Dlaka·James McDougall·James Y Tai·Petros Androvitsaneas·Edmund Harbord·Ruth Oulton·Andrew B. Young
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Abstract

Quantum dots in micropillars are one of the most promising options for a bright, deterministic single photon source. While highly efficient devices (>95%) have been designed, there remains a significant bottleneck that impacts the overall system efficiency: the large numerical aperture of the output mode. This leads to inefficient coupling of emitted photons into single-mode fibre, thus limiting practical integration into quantum computing and communication architectures. We show that with the addition of a well designed aspheric SiO2 microlens we can decrease the mode-matching losses to a SMF from 83.1% to <0.1(0.1)%. This can result in a single photon source design with 96.4(0.1)% end-to-end efficiency, paving the way for scalable photonic quantum technologies.

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BibTeXRIS

Yichen Zhang, David Dlaka, James McDougall, James Y Tai, Petros Androvitsaneas, Edmund Harbord, Ruth Oulton, Andrew B. Young. 2025-08-08. Aspheric lens design proposal for near-perfect mode-matching of a broadband quantum dot micropillar to a single-mode fibre. https://arxiv.org/abs/2508.06223

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