Enhancing quantum cryptography with quantum dot single-photon sources

Mathieu Bozzio (Corresponding author), Michal Vyvlecka (Corresponding author), Michael Cosacchi, Cornelius Nawrath, Tim Seidelmann, Juan C. Loredo, Simone L. Portalupi, Vollrath M. Axt, Peter Michler, Philip Walther

Publications: Contribution to journalArticlePeer Reviewed


Quantum cryptography harnesses quantum light, in particular single photons, to provide security guarantees that cannot be reached by classical means. For each cryptographic task, the security feature of interest is directly related to the photons' non-classical properties. Quantum dot-based single-photon sources are remarkable candidates, as they can in principle emit deterministically, with high brightness and low multiphoton contribution. Here, we show that these sources provide additional security benefits, thanks to the tunability of coherence in the emitted photon-number states. We identify the optimal optical pumping scheme for the main quantum-cryptographic primitives, and benchmark their performance with respect to Poisson-distributed sources such as attenuated laser states and down-conversion sources. In particular, we elaborate on the advantage of using phonon-assisted and two-photon excitation rather than resonant excitation for quantum key distribution and other primitives. The presented results will guide future developments in solid-state and quantum information science for photon sources that are tailored to quantum communication tasks.
Original languageEnglish
Article number104
Number of pages8
Journalnpj Quantum Information
Issue number1
Publication statusPublished - 8 Sep 2022

Austrian Fields of Science 2012

  • 103025 Quantum mechanics
  • 103026 Quantum optics



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