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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
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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.

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Denis Fatkhiev, Alexander Grebenchukov, João dos Reis Frazão, Gleb Nazarikov, Chigo Okonkwo, Idelfonso Tafur Monroy. 2026-06-19. Time-Bin BB84 QKD System Using Indium Phosphide and Silicon Nitride Photonic Integrated Circuits. https://arxiv.org/abs/2606.21308

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