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arXiv · 1608.04220

Experimental transmission of quantum digital signatures over 90-km of installed optical fiber using a differential phase shift quantum key distribution system

Robert J. Collins·Ryan Amiri·Mikio Fujiwara·Toshimori Honjo·Kaoru Shimizu·Kiyoshi Tamaki·Masahiro Takeoka·Erika Andersson·Gerald S. Buller·Masahide Sasaki
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Abstract

Quantum digital signatures apply quantum mechanics to the problem of guaranteeing message integrity and non-repudiation with information-theoretical security, which are complementary to the confidentiality realized by quantum key distribution. Previous experimental demonstrations have been limited to transmission distances of less than 5-km of optical fiber in a laboratory setting. Here we report the first demonstration of quantum digital signatures over installed optical fiber as well as the longest transmission link reported to date. This demonstration used a 90-km long differential phase shift quantum key distribution system to achieve approximately one signed bit per second - an increase in the signature generation rate of several orders of magnitude over previous optical fiber demonstrations.

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Robert J. Collins, Ryan Amiri, Mikio Fujiwara, Toshimori Honjo, Kaoru Shimizu, Kiyoshi Tamaki, Masahiro Takeoka, Erika Andersson, Gerald S. Buller, Masahide Sasaki. 2016-08-15. Experimental transmission of quantum digital signatures over 90-km of installed optical fiber using a differential phase shift quantum key distribution system. https://doi.org/10.1364/ol.41.004883

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