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arXiv:quant-ph/0608042 · Physical Review Letters

Secret Quantum Communication of a Reference Frame

Giulio Chiribella, Lorenzo Maccone, Paolo Perinotti

Published Mar 19, 2007• 19 citations
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Abstract

We propose quantum-cryptographic protocols to secretly communicate a reference frame--unspeakable information in the sense it cannot be encoded into a string of bits. Two distant parties can secretly align their Cartesian axes by exchanging N spin-1/2 particles, achieving the optimal accuracy 1/N. A possible eavesdropper cannot gain any information without being detected.

DOI
10.1103/physrevlett.98.120501

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We propose quantum-cryptographic protocols to secretly communicate a reference frame--unspeakable information in the sense it cannot be encoded into a string of bits. Two distant parties can secretly align their Cartesian axes by exchanging N spin-1/2 particles, achieving the optimal accuracy 1/N. A possible eavesdropper cannot gain any information without being detected.
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