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arXiv · 1005.1242

Quantum mechanical effect of path-polarization contextuality for a single photon

Alok Kumar Pan·Dipankar Home
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Abstract

Using measurements pertaining to a suitable Mach-Zehnder(MZ) type setup, a curious quantum mechanical effect of contextuality between the path and the polarization degrees of freedom of a polarized photon is demonstrated, without using any notion of realism or hidden variables - an effect that holds good for the product as well as the entangled states. This form of experimental context-dependence is manifested in a way such that at \emph{either} of the two exit channels of the MZ setup used, the empirically verifiable \emph{subensemble} statistical properties obtained by an arbitrary polarization measurement depend upon the choice of a commuting(comeasurable) path observable, while this effect disappears for the \emph{whole ensemble} of photons emerging from the two exit channels of the MZ setup.

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Alok Kumar Pan, Dipankar Home. 2010-05-07. Quantum mechanical effect of path-polarization contextuality for a single photon. https://doi.org/10.1007/s10773-010-0376-4

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