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arXiv · 0802.3183

Violation of the Cauchy-Schwarz Inequality in the Macroscopic Regime

A. M. Marino·V. Boyer·P. D. Lett
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Abstract

We have observed a violation of the Cauchy-Schwarz inequality in the macroscopic regime by more than 8 standard deviations. The violation has been obtained while filtering out only the low frequency noise of the quantum-correlated beams that results from the technical noise of the laser used to generate them. We use bright intensity-difference squeezed beams produced by four-wave mixing as the source of the correlated fields. We also demonstrate that squeezing does not necessarily imply a violation of the Cauchy-Schwarz inequality.

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A. M. Marino, V. Boyer, P. D. Lett. 2008-02-21. Violation of the Cauchy-Schwarz Inequality in the Macroscopic Regime. https://doi.org/10.1103/physrevlett.100.233601

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