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arXiv · 2606.31775

Energy-time entanglement from a monolithically integrated quantum dot on silicon

Marcel Hohn·Imad Limame·Peter Ludewig·Chirag C. Palekar·Aris Koulas-Simos·Kerstin Volz·Stephan Reitzenstein
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Abstract

Scalable quantum photonic technologies require deterministic sources of entangled photons that are compatible with established semiconductor manufacturing platforms. While self-assembled III--V semiconductor quantum dots are among the most promising sources of on-demand entanglement generation, their integration with silicon-based architectures remains a central challenge. Here, we demonstrate energy--time entanglement from a single InGaAs/GaAs quantum dot monolithically grown on a silicon substrate. Under coherent two-photon excitation, we achieve coherent control of the biexciton--exciton cascade, evidenced by Rabi oscillations and dressed-state formation. Using a four-channel Franson interferometer, we observe phase-dependent two-photon interference with visibilities up to $(64.0 \pm 7.0)\%$ for an 80 ps integration window (and $(49.4 \pm 1.9)\%$ for a 1600 ps window), approaching the threshold for Bell inequality violation at short time scales. These results establish monolithically integrated III--V-on-silicon quantum dots as promising sources of energy--time entangled photons for scalable quantum photonic technologies.

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Marcel Hohn, Imad Limame, Peter Ludewig, Chirag C. Palekar, Aris Koulas-Simos, Kerstin Volz, Stephan Reitzenstein. 2026-06-30. Energy-time entanglement from a monolithically integrated quantum dot on silicon. https://arxiv.org/abs/2606.31775

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