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Observation of Four-Photon de Broglie Wavelength by State Projection Measurement

F. W. Sun·B. H. Liu·Y. F. Huang·Z. Y. Ou·G. C. Guo
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Abstract

A measurement process is constructed to project an arbitrary two-mode $N$-photon state to a maximally entangled $N$-photon state (the {\it NOON}-state). The result of this projection measurement shows a typical interference fringe with an $N$-photon de Broglie wavelength. For an experimental demonstration, this measurement process is applied to a four-photon superposition state from two perpendicularly oriented type-I parametric down-conversion processes. Generalization to arbitrary $N$-photon states projection measurement can be easily made and may have wide applications in quantum information. As an example, we formulate it for precision phase measurement.

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F. W. Sun, B. H. Liu, Y. F. Huang, Z. Y. Ou, G. C. Guo. 2005-12-23. Observation of Four-Photon de Broglie Wavelength by State Projection Measurement. https://doi.org/10.1103/physreva.74.033812

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