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arXiv · 2512.14408

Capacity and SKR tradeoff in coexisting classical and CV-QKD metropolitan-reach optical links

Cagla Ozkan·Lucas Alves Zischler·Kadir Gumus·Joao dos Reis Frazao·Cristian Antonelli·Chigo Okonkwo
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Abstract

We demonstrate power-regime-dependent guardband optimization for quantum-classical coexistence in metropolitan DWDM. Quantum channel at band-edge with 100-150 GHz guardbands achieves 108% SKR improvement at -1.5 dBm/ch, incurring 3.4% capacity loss versus 6.8% for band-center.

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Cagla Ozkan, Lucas Alves Zischler, Kadir Gumus, Joao dos Reis Frazao, Cristian Antonelli, Chigo Okonkwo. 2025-12-16. Capacity and SKR tradeoff in coexisting classical and CV-QKD metropolitan-reach optical links. https://arxiv.org/abs/2512.14408

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