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arXiv · 0705.4177

Path-phase duality of an interfering particle with translational-internal entanglement

M. Kolar·T. Opatrny·N. Bar-Gill·N. Erez·G. Kurizki
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Abstract

The aim of this paper is to revisit the implications of complementarity when we inject into a Mach Zehnder interferometer particles with internal structure, prepared in special translational-internal entangled (TIE) states. This correlation causes the path distinguishability to be phase dependent in contrast to the standard case. We show that such a TIE state permits us to detect small phase shifts along with almost perfect path distinguishability, beyond the constraints imposed by complementarity on simultaneous which-way and which-phase measurements for standard cases (when distinguishability is independent of interferometric phase).

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M. Kolar, T. Opatrny, N. Bar-Gill, N. Erez, G. Kurizki. 2007-05-29. Path-phase duality of an interfering particle with translational-internal entanglement. https://doi.org/10.1088/1367-2630%2F9%2F5%2F129

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