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arXiv · 2305.13273

Robust excitation of C-band quantum dots for quantum communication

Michal Vyvlecka·Lennart Jehle·Cornelius Nawrath·Francesco Giorgino·Mathieu Bozzio·Robert Sittig·Michael Jetter·Simone L. Portalupi·Peter Michler·Philip Walther
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Abstract

Building a quantum internet requires efficient and reliable quantum hardware, from photonic sources to quantum repeaters and detectors, ideally operating at telecommunication wavelengths. Thanks to their high brightness and single-photon purity, quantum dot (QD) sources hold the promise to achieve high communication rates for quantum-secured network applications. Furthermore, it was recently shown that excitation schemes, such as longitudinal acoustic phonon-assisted (LA) pumping, provide security benefits by scrambling the coherence between the emitted photon-number states. In this work, we investigate further advantages of LA-pumped quantum dots with emission in the telecom C-band as a core hardware component of the quantum internet. We experimentally demonstrate how varying the pump energy and spectral detuning with respect to the excitonic transition can improve quantum-secured communication rates and provide stable emission statistics regardless of network-environment fluctuations. These findings have significant implications for general implementations of QD single-photon sources in practical quantum communication networks.

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Michal Vyvlecka, Lennart Jehle, Cornelius Nawrath, Francesco Giorgino, Mathieu Bozzio, Robert Sittig, Michael Jetter, Simone L. Portalupi, Peter Michler, Philip Walther. 2023-11-03. Robust excitation of C-band quantum dots for quantum communication. https://doi.org/10.1063/5.0166285

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