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arXiv · 2111.06068

Coherence, Path-Predictability and I-Concurrence: A Triality

Abhinash Kumar Roy·Neha Pathania·Nitish Kumar Chandra·Prasanta K. Panigrahi·Tabish Qureshi
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Abstract

It is well known that fringe contrast is not a good quantifier of the wave nature of a quanton in multipath interference. A new interference visibility, based on the Hilbert-Schmidt coherence is introduced. It is demonstrated that this visibility is a good quantifier of wave nature, and can be experimentally measured. A generalized path predictability is introduced, which reduces to the predictability of Greenberger and Yasin, for the case of two paths. In a multipath, which-way interference experiment, the new visibility, the predictability and the I-concurrence (quantifying the entanglement between the quanton and the path-detector), are shown to follow a tight triality relation. It quantifies the essential role that entanglement plays in multipath quantum complementarity, for the first time.

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Abhinash Kumar Roy, Neha Pathania, Nitish Kumar Chandra, Prasanta K. Panigrahi, Tabish Qureshi. 2021-11-11. Coherence, Path-Predictability and I-Concurrence: A Triality. https://doi.org/10.1103/physreva.105.032209

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