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Quantum key distribution with 2-bit quantum codes

Xiang-Bin Wang
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Abstract

We propose a prepare-and-measure scheme for quantum key distribution with 2-bit quantum codes. The protocol is unconditionally secure under whatever type of intercept-and-resend attack. Given the symmetric and independent errors to the transmitted qubits, our scheme can tolerate a bit error rate up to 26% in 4-state protocol and 30% in 6-state protocol, respectively. These values are higher than all currently known threshold values for prepare-and-measure protocols. A specific realization with linear optics is given.

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Xiang-Bin Wang. 2004-01-04. Quantum key distribution with 2-bit quantum codes. https://doi.org/10.1103/physrevlett.92.077902

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