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arXiv:2504.08285 · Optical Fiber Communication Conference

World's First Monolithic SiGe QKD Transmitter Chip

Florian Honz, W. Boxleitner, Mariana F. Ramos, Michael Hentschel, Philip John Walther, Hannes Hübel, Bernhard Schrenk

Published Jan 1, 2025• 2 citations
arXivHTMLPDF

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.
DOI
10.1364/ofc.2025.th4d.7

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We present a silicon optical transmitter for polarization-encoded quantum key distribution (QKD). The chip was fabricated in a standard silicon photonic foundry process and integrated a pulse generator, intensity modulator, variable optical attenuator, and polarization modulator in a 1.3 mm ×\times× 3 mm die area. The devices in the photonic circuit meet the requirements for QKD. The transmitter was used in a proof-of-concept demonstration of the BB84 QKD protocol over a 5 km long fiber link.
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