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Planar lightwave circuits for quantum cryptographic systems

Yoshihiro Nambu·Takaaki Hatanaka·Kazuo Nakamura
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Abstract

We propose a quantum cryptographic system based on a planar lightwave circuit (PLC) and report on optical interference experiments using PLC-based unbalanced Mach-Zehnder interferometers (MZIs). The interferometers exhibited high-visibility (>0.98) interference even when the polarisation in the optical fibre connecting the two MZIs was randomly modulated. The results demonstrate that a PLC-based setup is suitable for achieving a polarisation-insensitive phase-coding cryptographic system.

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Yoshihiro Nambu, Takaaki Hatanaka, Kazuo Nakamura. 2003-07-10. Planar lightwave circuits for quantum cryptographic systems. https://arxiv.org/abs/quant-ph/0307074

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