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arXiv · 2005.13015

Noisy pre-processing facilitating a photonic realisation of device-independent quantum key distribution

M. Ho·P. Sekatski·E. Y. -Z. Tan·R. Renner·J. -D. Bancal·N. Sangouard
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Abstract

Device-independent quantum key distribution provides security even when the equipment used to communicate over the quantum channel is largely uncharacterized. An experimental demonstration of device-independent quantum key distribution is however challenging. A central obstacle in photonic implementations is that the global detection efficiency, i.e., the probability that the signals sent over the quantum channel are successfully received, must be above a certain threshold. We here propose a method to significantly relax this threshold, while maintaining provable device-independent security. This is achieved with a protocol that adds artificial noise, which cannot be known or controlled by an adversary, to the initial measurement data (the raw key). Focusing on a realistic photonic setup using a source based on spontaneous parametric down conversion, we give explicit bounds on the minimal required global detection efficiency.

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M. Ho, P. Sekatski, E. Y. -Z. Tan, R. Renner, J. -D. Bancal, N. Sangouard. 2020-05-26. Noisy pre-processing facilitating a photonic realisation of device-independent quantum key distribution. https://doi.org/10.1103/physrevlett.124.230502

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