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arXiv · 2510.12761

Contextuality-based quantum key distribution with deterministic single-photon sources

Yu Meng·Debashis Saha·Mikkel Thorbjørn Mikkelsen·Clara Henke·Ying Wang·Nikolai Bart·Arne Ludwig·Peter Lodahl·Adán Cabello·Leonardo Midolo
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Abstract

Photons are central to quantum technologies, with photonic qubits offering a promising platform for quantum communication. Semiconductor quantum dots stand out for their ability to generate single photons on demand, a key capability for enabling long-distance quantum networks. In this work, we utilize high-purity single-photon sources based on self-assembled InAs(Ga)As quantum dots as quantum information carriers. We demonstrate that such on-demand single photons can generate quantum contextuality. This capability enables a novel protocol for semi-device-independent quantum key distribution over free-space channels. Crucially, our method does not require ideal or perfectly projective measurements, opening a new pathway for robust and practical quantum communication.

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Yu Meng, Debashis Saha, Mikkel Thorbjørn Mikkelsen, Clara Henke, Ying Wang, Nikolai Bart, Arne Ludwig, Peter Lodahl, Adán Cabello, Leonardo Midolo. 2025-10-14. Contextuality-based quantum key distribution with deterministic single-photon sources. https://arxiv.org/abs/2510.12761

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