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Quantum Cryptography: Security Criteria Reexamined

Dagomir Kaszlikowski·Ajay Gopinathan·Yeong Cherng Liang·L. C. Kwek·Berthold-Georg Englert
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Abstract

We find that the generally accepted security criteria are flawed for a whole class of protocols for quantum cryptography. This is so because a standard assumption of the security analysis, namely that the so-called square-root measurement is optimal for eavesdropping purposes, is not true in general. There are rather large parameter regimes in which the optimal measurement extracts substantially more information than the square-root measurement.

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Dagomir Kaszlikowski, Ajay Gopinathan, Yeong Cherng Liang, L. C. Kwek, Berthold-Georg Englert. 2004-09-06. Quantum Cryptography: Security Criteria Reexamined. https://doi.org/10.1103/physreva.70.032306

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