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arXiv · 0706.3902

Hierarchy of inequalities for quantitative duality

Jesus Martinez-Linares
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Abstract

We derive different relations quantifying duality in a generic two-way interferometer. These relations set different upper bounds to the visibility V of the fringes measured at the output port of the interferometer. A hierarchy of inequalities is presented which exhibits the influence of the availability to the experimenter of different sources of which-way information contributing to the total distinguishability D of the ways. For mixed states and unbalanced interferometers an inequality is derived, V^2+ Xi^2 \leq 1, which can be more stringent than the one associated with the distinguishability (V^2+ D^2 \leq 1).

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Jesus Martinez-Linares. 2007-06-26. Hierarchy of inequalities for quantitative duality. https://doi.org/10.1103/physreva.75.052112

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