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Experimental Proof of Quantum Nonlocality without Squeezing

J. Niset·A. Acin·U. L. Andersen·N. J. Cerf·R. García-Patrón·M. Navascues·M. Sabuncu
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Abstract

It is shown that the ensemble $\{p (α),|α>|α^*>\}$ where $p (α)$ is a Gaussian distribution of finite variance and $| α>$ is a coherent state can be better discriminated with an entangled measurement than with any local strategy supplemented by classical communication. Although this ensemble consists of products of quasi-classical states, it exhibits some quantum nonlocality. This remarkable effect is demonstrated experimentally by implementing the optimal local strategy together with a joint nonlocal strategy that yields a higher fidelity.

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J. Niset, A. Acin, U. L. Andersen, N. J. Cerf, R. García-Patrón, M. Navascues, M. Sabuncu. 2006-08-28. Experimental Proof of Quantum Nonlocality without Squeezing. https://doi.org/10.1103/physrevlett.98.260404

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