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arXiv:quant-ph/0403024 · Physical Review Letters

Experimental Demonstration of Entanglement-Enhanced Classical Communication over a Quantum Channel with Correlated Noise

Konrad Banaszek, Andrzej Dragan, Wojciech Wasilewski, Czesław Radzewicz

Published Jun 24, 2004• 127 citations
arXivHTMLPDF

Abstract

We present an experiment demonstrating the entanglement enhanced capacity of a quantum channel with correlated noise, modeled by a fiber optic link exhibiting fluctuating birefringence. In this setting, introducing entanglement between two photons is required to maximize the amount of information that can be encoded into their joint polarization degree of freedom. We demonstrated this effect using a fiber-coupled source of entangled photon pairs based on spontaneous parametric down-conversion, and a linear-optics Bell state measurement. The obtained experimental classical capacity with entangled states is equal to 0.82+/-0.04 per a photon pair, and it exceeds approximately 2.5 times the theoretical upper limit when no quantum correlations are allowed.

DOI
10.1103/physrevlett.92.257901

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