Security of quantum key distributions with entangled qudits

Journal Article · Mon Mar 01 04:00:00 EST 2004 · Physical Review. A

DOI:https://doi.org/10.1103/PhysRevA.69.032313· OSTI ID:20640839

Durt, Thomas ^[1]; Kaszlikowski, Dagomir; Chen, Jing-Ling ^[2]; Kwek, L C ^[2]

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1. Toegepaste Natuurkunde en Fotonica, Theoretische Natuurkunde, Virje Universiteit Brussel, Pleinlaan 2, 1050 Brussels (Belgium)
2. Department of Physics, Faculty of Science, National University of Singapore, Lower Kent Ridge, Singapore 119260 (Singapore)

We consider a generalization of Ekert's entanglement-based quantum cryptographic protocol where qubits are replaced by N- or d-dimensional systems (qudits). In order to study its robustness against optimal incoherent attacks, we derive the information gained by a potential eavesdropper during a cloning-based individual attack. In doing so, we generalize Cerf's formalism for cloning machines and establish the form of the most general cloning machine that respects all the symmetries of the problem. We obtain an upper bound on the error rate that guarantees the confidentiality of qudit generalizations of the Ekert's protocol for qubits.

• OSTI ID: 20640839
• Journal Information: Physical Review. A, Journal Name: Physical Review. A Journal Issue: 3 Vol. 69; ISSN 1050-2947; ISSN PLRAAN
• Country of Publication: United States
• Language: English

Related Subjects

74 ATOMIC AND MOLECULAR PHYSICS
CORRELATIONS
DISTRIBUTION
ENERGY LEVELS
ERRORS
INFORMATION
INFORMATION THEORY
POTENTIALS
QUANTUM MECHANICS
SECRECY PROTECTION
SYMMETRY