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arXiv · 0708.0653

Experimental Violation of Bell's Inequality in Spatial-Parity Space

Timothy Yarnall·Ayman F. Abouraddy·Bahaa E. A. Saleh·Malvin C. Teich
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Abstract

We report the first experimental violation of Bell's inequality in the spatial domain using the Einstein--Podolsky--Rosen state. Two-photon states generated via optical spontaneous parametric downconversion are shown to be entangled in the parity of their one-dimensional transverse spatial profile. Superpositions of Bell states are prepared by manipulation of the optical pump's transverse spatial parity--a classical parameter. The Bell-operator measurements are made possible by devising simple optical arrangements that perform rotations in the one-dimensional spatial-parity space of each photon of an entangled pair and projective measurements onto a basis of even--odd functions. A Bell-operator value of 2.389 +- 0.016 is recorded, a violation of the inequality by more than 24 standard deviations.

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Timothy Yarnall, Ayman F. Abouraddy, Bahaa E. A. Saleh, Malvin C. Teich. 2007-08-05. Experimental Violation of Bell's Inequality in Spatial-Parity Space. https://doi.org/10.1103/physrevlett.99.170408

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