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arXiv · 2607.11252

Deployment of Entanglement-Based QKD in Financial Infrastructure

Mirela Selimović·Roman Solar·Jonathan Gruner·Sebastian Mair·Mario Wenzl·Thomas Heine·Matej Pivoluska·Rupert Ursin·Sebastian Philipp Neumann
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Abstract

We demonstrate the feasibility of entanglement-based quantum key distribution (eQKD) in high-security financial infrastructure over a 22 km fiber link with 8 dB loss between two data centers using polarization entanglement. The fully automated system continuously generated secure keys for four months at an average rate of 63.8 kb/s, which were stored into a key management system and consumed to establish a VPN tunnel. The setup achieved 93.7% total up-time, with no downtime caused by the quantum optical components. Active polarization control kept the quantum bit error rate below 2% for 97.4% of the time and timing synchronization based on the entangled photon pairs' intrinsic temporal correlations achieved sub-300 ps precision. Our standalone system requires neither polarized guide lasers nor external high-precision time references. These results show practical integration of eQKD into operational financial infrastructure.

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Mirela Selimović, Roman Solar, Jonathan Gruner, Sebastian Mair, Mario Wenzl, Thomas Heine, Matej Pivoluska, Rupert Ursin, Sebastian Philipp Neumann. 2026-07-13. Deployment of Entanglement-Based QKD in Financial Infrastructure. https://arxiv.org/abs/2607.11252

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