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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.
Citation
Physical Review Letters
Volume
100

Keywords

alkali vapor, classical inequality, electromagnetically-induced transparancy, four-wave mixing, nonclassical light, squeezed light

Citation

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 December 1, 2021)
Created June 10, 2008, Updated February 17, 2017