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arXiv · 1405.5721

Three-Slit Interference: A Duality Relation

Mohd Asad Siddiqui·Tabish Qureshi
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Abstract

The issue of interference and which-way information is addressed in the context of 3-slit interference experiments. A new path distinguishability ${\mathcal D_Q}$ is introduced, based on Unambiguous Quantum State Discrimination (UQSD). An inequality connecting the interference visibility and path distinguishability, ${\mathcal V} + {2{\mathcal D_Q}\over 3- {\mathcal D_Q}} \le 1$, is derived which puts a bound on how much fringe visibility and which-way information can be simultaneously obtained. It is argued that this bound is tight. For 2-slit interference, we derive a new duality relation which reduces to Englert's duality relation and Greenberger-Yasin's duality relation, in different limits.

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Mohd Asad Siddiqui, Tabish Qureshi. 2014-05-22. Three-Slit Interference: A Duality Relation. https://doi.org/10.1093/ptep%2Fptv112

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