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arXiv · 0807.5079

Illustration of quantum complementarity using single photons interfering on a grating

V. Jacques·N. D. Lai·A. Dreau·D. Zheng·D. Chauvat·F. Treussart·P. Grangier·J-F Roch
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Abstract

A recent experiment performed by S. S. Afshar et al. has been interpreted as a violation of Bohr's complementarity principle between interference visibility and which-path information in a two-path interferometer. We have reproduced this experiment, using true single-photon pulses propagating in a two-path wavefront- splitting interferometer realized with a Fresnel's biprism, and followed by a grating with adjustable transmitting slits. The measured values of interference visibility V and which-path information, characterized by the distinguishability parameter D, are found to obey the complementarity relation V^2+D^2=<1. This result demonstrates that the experiment can be perfectly explained by the Copenhagen interpretation of quantum mechanics.

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V. Jacques, N. D. Lai, A. Dreau, D. Zheng, D. Chauvat, F. Treussart, P. Grangier, J-F Roch. 2009-02-10. Illustration of quantum complementarity using single photons interfering on a grating. https://doi.org/10.1088/1367-2630%2F10%2F12%2F123009

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