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arXiv · 1811.04198

Experimental wavelength-space division multiplexing of quantum key distribution with classical optical communication over multicore fiber

Chun Cai·Yongmei Sun·Yongrui Zhang·Peng Zhang·Jianing Niu·Yuefeng Ji
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Abstract

We demonstrate quantum key distribution (QKD) with classical signals in a seven-core fiber using dense wavelength division multiplexing. Quantum signals are transmitted in an outer core separately and intercore crosstalk (IC-XT) is the main impairment of them. In order to alleviate IC-XT, we propose a quantum-classical interleave scheme. Then the properties of IC-XT are analyzed based on the measurement results which indicate counter-propagation is a better co-existence method than co-propagation. Finally, we perform QKD experiments in the presence of two classical channels with a channel spacing of 100 GHz between quantum channel and the nearest classical channels. The experiment results prove counter-propagation almost immune to IC-XT, which is consistent with our analysis. Also, the feasibility of the transmission over the range of metropolitan area networks is validated with our scheme.

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Chun Cai, Yongmei Sun, Yongrui Zhang, Peng Zhang, Jianing Niu, Yuefeng Ji. 2018-11-10. Experimental wavelength-space division multiplexing of quantum key distribution with classical optical communication over multicore fiber. https://doi.org/10.1364/oe.27.005125

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