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Super-resolving phase measurements with a multi-photon entangled state

M. W. Mitchell·J. S. Lundeen·A. M. Steinberg
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Abstract

Using a linear optical elements and post-selection, we construct an entangled polarization state of three photons in the same spatial mode. This state is analogous to a ``photon-number path entangled state'' and can be used for super-resolving interferometry. Measuring a birefringent phase shift, we demonstrate two- and three-fold improvements in phase resolution.

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M. W. Mitchell, J. S. Lundeen, A. M. Steinberg. 2003-12-22. Super-resolving phase measurements with a multi-photon entangled state. https://doi.org/10.1038/nature02493

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