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arXiv · 2504.08285

World's First Monolithic SiGe QKD Transmitter Chip

Florian Honz·Winfried Boxleitner·Mariana Ferreira-Ramos·Michael Hentschel·Philip Walther·Hannes Hübel·Bernhard Schrenk
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Abstract

We present a single-chip photonic QKD transmitter fabricated on a silicon platform. We achieve secure-key generation over 45.9km of field-deployed fiber and prove its operation along 32 WDM channels, by sourcing light without III-V materials.

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Florian Honz, Winfried Boxleitner, Mariana Ferreira-Ramos, Michael Hentschel, Philip Walther, Hannes Hübel, Bernhard Schrenk. 2025-04-11. World's First Monolithic SiGe QKD Transmitter Chip. https://arxiv.org/abs/2504.08285

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