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The Faraday Quantum Clock and Non-local Photon Pair Correlations

Y. Japha·G. Kurizki
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Abstract

We study the use of the Faraday effect as a quantum clock for measuring traversal times of evanescent photons through magneto-refractive structures. The Faraday effect acts both as a phase-shifter and as a filter for circular polarizations. Only measurements based on the Faraday phase-shift properties are relevant to the traversal time measurements. The Faraday polarization filtering may cause the loss of non-local (Einstein-Podolsky-Rosen) two-photon correlations, but this loss can be avoided without sacrificing the clock accuracy. We show that a mechanism of destructive interference between consecutive paths is responsible for superluminal traversal times measured by the clock.

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Y. Japha, G. Kurizki. 1999-04-12. The Faraday Quantum Clock and Non-local Photon Pair Correlations. https://doi.org/10.1103/physreva.60.1811

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