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arXiv · 1109.2508

Hybrid ququart-encoded quantum cryptography protected by Kochen-Specker contextuality

Adan Cabello·Vincenzo D'Ambrosio·Eleonora Nagali·Fabio Sciarrino
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Abstract

Quantum cryptographic protocols based on complementarity are nonsecure against attacks in which complementarity is imitated with classical resources. The Kochen-Specker (KS) theorem provides protection against these attacks, without requiring entanglement or spatially separated composite systems. We analyze the maximum tolerated noise to guarantee the security of a KS-protected cryptographic scheme against these attacks, and describe a photonic realization of this scheme using hybrid ququarts defined by the polarization and orbital angular momentum of single photons.

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Adan Cabello, Vincenzo D'Ambrosio, Eleonora Nagali, Fabio Sciarrino. 2011-09-12. Hybrid ququart-encoded quantum cryptography protected by Kochen-Specker contextuality. https://doi.org/10.1103/physreva.84.030302

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