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Single-qubit optical quantum fingerprinting

Rolf T. Horn·S. A. Babichev·Karl-Peter Marzlin·A. I. Lvovsky·Barry C. Sanders
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Abstract

We analyze and demonstrate the feasibility and superiority of linear optical single-qubit fingerprinting over its classical counterpart. For one-qubit fingerprinting of two-bit messages, we prepare `tetrahedral' qubit states experimentally and show that they meet the requirements for quantum fingerprinting to exceed the classical capability. We prove that shared entanglement permits 100% reliable quantum fingerprinting, which will outperform classical fingerprinting even with arbitrary amounts of shared randomness.

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Rolf T. Horn, S. A. Babichev, Karl-Peter Marzlin, A. I. Lvovsky, Barry C. Sanders. 2004-10-27. Single-qubit optical quantum fingerprinting. https://doi.org/10.1103/physrevlett.95.150502

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