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arXiv · 1103.2327

Device calibration impacts security of quantum key distribution

Nitin Jain·Christoffer Wittmann·Lars Lydersen·Carlos Wiechers·Dominique Elser·Christoph Marquardt·Vadim Makarov·Gerd Leuchs
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Abstract

Characterizing the physical channel and calibrating the cryptosystem hardware are prerequisites for establishing a quantum channel for quantum key distribution (QKD). Moreover, an inappropriately implemented calibration routine can open a fatal security loophole. We propose and experimentally demonstrate a method to induce a large temporal detector efficiency mismatch in a commercial QKD system by deceiving a channel length calibration routine. We then devise an optimal and realistic strategy using faked states to break the security of the cryptosystem. A fix for this loophole is also suggested.

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Nitin Jain, Christoffer Wittmann, Lars Lydersen, Carlos Wiechers, Dominique Elser, Christoph Marquardt, Vadim Makarov, Gerd Leuchs. 2011-09-16. Device calibration impacts security of quantum key distribution. https://doi.org/10.1103/physrevlett.107.110501

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