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arXiv · 1902.00811

Scalable high-rate, high-dimensional quantum key distribution

Nurul T. Islam·Charles Ci Wen Lim·Clinton Cahall·Bing Qi·Jungsang Kim·Daniel J. Gauthier
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Abstract

We propose and experimentally demonstrate a new scheme for measuring high-dimensional phase states using a two-photon interference technique, which we refer to as quantum-controlled measurement. Using this scheme, we implement a $d$-dimensional time-phase quantum key distribution (QKD) system and achieve secret key rates of 5.26 and 8.65 Mbps using $d = 2$ and $d = 8$ quantum states, respectively, for a 4~dB channel loss, illustrating that high-dimensional time-phase QKD protocols are advantageous for low-loss quantum channels. This work paves the way for practical high-dimensional QKD protocols for metropolitan-scale systems. Furthermore, our results apply equally well for other high-dimensional protocols, such as those using the spatial degree-of-freedom with orbital angular momentum states being one example.

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Nurul T. Islam, Charles Ci Wen Lim, Clinton Cahall, Bing Qi, Jungsang Kim, Daniel J. Gauthier. 2019-02-02. Scalable high-rate, high-dimensional quantum key distribution. https://arxiv.org/abs/1902.00811

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