Optics Express

Field implementation of long-distance quantum key distribution over aerial fiber with fast polarization feedback

Dong-Dong Li, Song Gao, Guo-Chun Li, Lu Xue, Liwei Wang, Changbin Lu, Yao Xiang, Ziyan Zhao, Longchuan Yan, Zhiyu Chen, Gang Yu, Jian-Hong Liu

Published Aug 21, 2018• 60 citations

Publisher

Abstract

Quantum key distribution with polarized qubits has not yet been realized over the aerial fiber, due to rapid polarization changes. Here, we report our recent work towards quantum communication through an aerial fiber channel. We designed a fast polarization feedback module featuring high efficiency, fast speed, and good stability. With this module, we implemented long-distance quantum key distribution over different types of aerial fiber links based on polarization encoding. Our work takes a significant step towards the application of quantum communications in complex environments.

DOI: 10.1364/oe.26.022793

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