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Quantum cryptography with 3-state systems

Helle Bechmann-Pasquinucci·Asher Peres
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Abstract

We consider quantum cryptographic schemes where the carriers of information are 3-state particles. One protocol uses four mutually unbiased bases and appears to provide better security than obtainable with 2-state carriers. Another possible method allows quantum states to belong to more than one basis. The security is not better, but many curious features arise.

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Helle Bechmann-Pasquinucci, Asher Peres. 2000-01-23. Quantum cryptography with 3-state systems. https://doi.org/10.1103/physrevlett.85.3313

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