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arXiv:2606.21308

Time-Bin BB84 QKD System Using Indium Phosphide and Silicon Nitride Photonic Integrated Circuits

Denis Fatkhiev, Alexander Grebenchukov, João dos Reis Frazão, Gleb Nazarikov, Chigo Okonkwo, Idelfonso Tafur Monroy

quant-phSubmitted Jun 19, 2026• Announced Jun 22, 2026• 0 citations
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Abstract

We demonstrate a dual-chip InP-SiN photonic QKD system with on-chip pulse generation and reconfigurable decoding, implementing time-bin BB84 with finite-key security against coherent attacks. The system sustains a QBER below 4% and delivers secret keys at kbps rates over 150-250 km of fiber.
Comments
Accepted for presentation at European Conference on Optical Communications (ECOC) 2026

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