2010/06/30 by Bing Qi, Wen Zhu, Li Qian +2 · 191 citations
Computer Science · Engineering · Physics and Astronomy · #BB84 #Channel (broadcasting) #Computer science #Detector #Electronic engineering #Engineering #Homodyne detection #Multiplexing #Optics #Photon #Physics #Quantum #Quantum Information and Cryptography #Quantum Mechanics and Applications #Quantum channel #Quantum entanglement #Quantum key distribution #Quantum mechanics #Quantum optics and atomic interactions #Telecommunications #Wavelength #Wavelength-division multiplexing #quant-ph
paper · pdf · open access · doi:10.1088/1367-2630/12/10/103042
published in New Journal of Physics 12(10), 103042 (IOP Publishing) · 18 pages, 5 figures
arxiv created 2010/10/01 · openalex publication_date 2010/10/27 · arxiv updated 2015/05/19 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
In this paper, we study the feasibility of conducting quantum key distribution (QKD) together with classical communication through the same optical fiber by employing dense-wavelength-division-multiplexing (DWDM) technology at telecom wavelength. The impact of the classical channels to the quantum channel has been investigated for both QKD based on single photon detection and QKD based on homodyne detection. Our studies show that the latter can tolerate a much higher level of contamination from the classical channels than the former. This is because the local oscillator used in the homodyne detector acts as a "mode selector" which can suppress noise photons effectively. We have performed simulations based on both the decoy BB84 QKD protocol and the Gaussian modulated coherent state (GMCS) QKD protocol. While the former cannot tolerate even one classical channel (with a power of 0dBm), the latter can be multiplexed with 38 classical channels (0dBm power each channel) and still has a secure distance around 10km. Preliminary experiment has been conducted based on a 100MHz bandwidth homodyne detector.