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arXiv · 1109.1203

Improved Data Post-Processing in Quantum Key Distribution and Application to Loss Thresholds in Device Independent QKD

Xiongfeng Ma·Norbert Lütkenhaus
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Abstract

Security proofs of quantum key distribution (QKD) often require post-processing schemes to simplify the data structure, and hence the security proof. We show a generic method to improve resulting secure key rates by partially reversing the simplifying post-processing for error correction purposes. We apply our method to the security analysis of device-independent QKD schemes and of detection-device-independent QKD schemes, where in both cases one is typically required to assign binary values even to lost signals. In the device-independent case, the loss tolerance threshold is cut down by our method from 92.4% to 90.9%.The lowest tolerable transmittance of the detector-device-independent scheme can be improved from 78.0% to 65.9%.

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Xiongfeng Ma, Norbert Lütkenhaus. 2011-09-06. Improved Data Post-Processing in Quantum Key Distribution and Application to Loss Thresholds in Device Independent QKD. https://arxiv.org/abs/1109.1203

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