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arXiv · 1208.0023

Device-Independent Quantum Key Distribution with Local Bell Test

Charles Ci Wen Lim·Christopher Portmann·Marco Tomamichel·Renato Renner·Nicolas Gisin
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Abstract

Device-independent quantum key distribution (DIQKD) in its current design requires a violation of Bell's inequality between two honest parties, Alice and Bob, who are connected by a quantum channel. However, in reality, quantum channels are lossy, and this can be exploited for attacks based on the detection loophole. Here, we propose a novel approach to DIQKD that overcomes this limitation. In particular, based on a combination between an entropic uncertainty relation and the Clauser-Horne-Shimony-Holt (CHSH) test, we design a DIQKD protocol where the CHSH test is carried out entirely in Alice's laboratory. Thus the loophole caused by channel losses is avoided.

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Charles Ci Wen Lim, Christopher Portmann, Marco Tomamichel, Renato Renner, Nicolas Gisin. 2012-07-31. Device-Independent Quantum Key Distribution with Local Bell Test. https://doi.org/10.1103/physrevx.3.031006

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