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arXiv · 0907.1679

Violation of the Leggett-Garg inequality with weak measurements of photons

M. E. Goggin·M. P. Almeida·M. Barbieri·B. P. Lanyon·J. L. O'Brien·A. G. White·G. J. Pryde
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Abstract

By weakly measuring the polarization of a photon between two strong polarization measurements, we experimentally investigate the correlation between the appearance of anomalous values in quantum weak measurements, and the violation of realism and non-intrusiveness of measurements. A quantitative formulation of the latter concept is expressed in terms of a Leggett-Garg inequality for the outcomes of subsequent measurements of an individual quantum system. We experimentally violate the Leggett-Garg inequality for several measurement strengths. Furthermore, we experimentally demonstrate that there is a one-to-one correlation between achieving strange weak values and violating the Leggett-Garg inequality.

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M. E. Goggin, M. P. Almeida, M. Barbieri, B. P. Lanyon, J. L. O'Brien, A. G. White, G. J. Pryde. 2009-07-09. Violation of the Leggett-Garg inequality with weak measurements of photons. https://doi.org/10.1073/pnas.1005774108

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