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Experimental quantum communication complexity

Pavel Trojek·Christian Schmid·Mohamed Bourennane·Caslav Brukner·Marek Zukowski·Harald Weinfurter
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Abstract

We prove that the fidelity of two exemplary communication complexity protocols, allowing for an N-1 bit communication, can be exponentially improved by N-1 (unentangled) qubit communication. Taking into account, for a fair comparison, all inefficiencies of state-of-the-art set-up, the experimental implementation outperforms the best classical protocol, making it the candidate for multi-party quantum communication applications.

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Pavel Trojek, Christian Schmid, Mohamed Bourennane, Caslav Brukner, Marek Zukowski, Harald Weinfurter. 2005-02-11. Experimental quantum communication complexity. https://doi.org/10.1103/physreva.72.050305

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