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arXiv · 2301.01706

On-chip Hong-Ou-Mandel interference from separate quantum dot emitters in an integrated circuit

Łukasz Dusanowski·Dominik Köck·Christian Schneider·Sven Höfling
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Abstract

Scalable quantum photonic technologies require low-loss integration of many identical single-photon sources with photonic circuitry on a chip. Relatively complex quantum photonic circuits have already been demonstrated; however, sources used so far relied on parametric-down-conversion. Hence, the efficiency and scalability are intrinsically limited by the probabilistic nature of the sources. Quantum emitter-based single-photon sources are free of this limitation, but frequency matching of multiple emitters within a single circuit remains a challenge. In this work, we demonstrate a key component in this regard in the form of a fully monolithic GaAs circuit combing two frequency-matched quantum dot single-photon sources interconnected with a low-loss on-chip beamsplitter connected via single-mode ridge waveguides. This device enabled us to perform a two-photon interference experiment on-chip with visibility reaching 66%, limited by the coherence of the emitters. Our device could be further scaled up, providing a clear path to increase the complexity of quantum circuits toward fully scalable integrated quantum technologies.

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Łukasz Dusanowski, Dominik Köck, Christian Schneider, Sven Höfling. 2023-01-04. On-chip Hong-Ou-Mandel interference from separate quantum dot emitters in an integrated circuit. https://arxiv.org/abs/2301.01706

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