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arXiv · 1411.1070

Practical high-dimensional quantum key distribution with decoy states

Darius Bunandar·Zheshen Zhang·Jeffrey H. Shapiro·Dirk R. Englund
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Abstract

High-dimensional quantum key distribution (HD-QKD) allows two parties to generate multiple secure bits of information per detected photon. In this work, we show that decoy state protocols can be practically implemented for HD-QKD using only one or two decoy states. HD-QKD with two decoy states, under realistic experimental constraints, can generate multiple secure bits per coincidence at distances over 200 km and at rates similar to those achieved by a protocol with infinite decoy states. Furthermore, HD-QKD with only one decoy state is practical at short distances, where it is almost as secure as a protocol with two decoy states. HD-QKD with only one or two decoy states can therefore be implemented to optimize the rate of secure quantum communications.

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Darius Bunandar, Zheshen Zhang, Jeffrey H. Shapiro, Dirk R. Englund. 2015-02-26. Practical high-dimensional quantum key distribution with decoy states. https://doi.org/10.1103/physreva.91.022336

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