Instantaneous dual-mode DFBLD wavelength deception for promoting decoyed DPS-QKD security

Yuan-Ren Yeh, Hsiao-Hui Chen, Yung-Hsuan Lee, Yu‐Chieh Chi, Yu-Sheng Liao, Chih-Hsien Cheng, Atsushi Matsumoto, Kouichi Akahane, Gong‐Ru Lin

Published Jan 1, 2026• 0 citations

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Abstract

Instantaneous dual-mode DFBLD wavelength switching with power and wavelength fluctuations of ±1.8×10⁻ 5 % and ±4×10⁻ 3 % is demonstrated for single-photon-level wavelength-deception DPS-QKD with a QBER of 2.8% and 3.1% under external and injection-locked DPS coding at 1-Gbps.

DOI: 10.1364/cleo_at.2026.jtu.118

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