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Violation of Cauchy-Schwarz Inequality in the Macroscopic Regime
Published
Author(s)
Alberto M. Marino, V Boyer, Paul D. Lett
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 correlated fields. We also show that squeezing does not necessarily imply a violation of the Cauchy-Schwarz inequality.
Marino, A.
, Boyer, V.
and Lett, P.
(2008),
Violation of Cauchy-Schwarz Inequality in the Macroscopic Regime, Physical Review Letters, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=842438
(Accessed October 14, 2025)