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Constructing CSS Codes with LDPC Codes for the BB84 Quantum Key Distribution Protocol

Maki Ohata·Kanta Matsuura
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Abstract

In this paper, we propose how to simply construct a pair of linear codes for the BB84 quantum key distribution protocol. This protocol allows unconditional security in the presence of an eavesdropper, and the pair of linear codes is used for error correction and privacy amplification. Since their high decoding performance implies low eavesdropper's mutual information, good design of the two codes is required. The proposed method admits using arbitrary low-density parity-check (LDPC) codes. Therefore, it has low complexity and high performance for hardware implementation. Simulation results show that the pair of codes performs well against practical and various noise levels.

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Maki Ohata, Kanta Matsuura. 2007-03-22. Constructing CSS Codes with LDPC Codes for the BB84 Quantum Key Distribution Protocol. https://arxiv.org/abs/quant-ph/0702184

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