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Quantitative wave-particle duality and non-erasing quantum erasure

Peter D. D. Schwindt·Paul G. Kwiat·Berthold-Georg Englert
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Abstract

The notion of wave-particle duality may be quantified by the inequality V^2+K^2 <=1, relating interference fringe visibility V and path knowledge K. With a single-photon interferometer in which polarization is used to label the paths, we have investigated the relation for various situations, including pure, mixed, and partially-mixed input states. A quantum eraser scheme has been realized that recovers interference fringes even when no which-way information is available to erase.

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Peter D. D. Schwindt, Paul G. Kwiat, Berthold-Georg Englert. 1999-08-23. Quantitative wave-particle duality and non-erasing quantum erasure. https://doi.org/10.1103/physreva.60.4285

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