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Security of Quantum Key Distribution with Entangled Qutrits

Thomas Durt·Nicolas J. Cerf·Nicolas Gisin·Marek Zukowski
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Abstract

The study of quantum cryptography and quantum non-locality have traditionnally been based on two-level quantum systems (qubits). In this paper we consider a generalisation of Ekert's cryptographic protocol [Ekert] where qubits are replaced by qutrits. The security of this protocol is related to non-locality, in analogy with Ekert's protocol. In order to study its robustness against the optimal individual attacks, we derive the information gained by a potential eavesdropper applying a cloning-based attack.

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Thomas Durt, Nicolas J. Cerf, Nicolas Gisin, Marek Zukowski. 2003-01-04. Security of Quantum Key Distribution with Entangled Qutrits. https://doi.org/10.1103/physreva.67.012311

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