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arXiv · 1604.06719

Correspondence: Enhancing a phase measurement by sequentially probing a solid state system

P. A. Knott·W. J. Munro·J. A. Dunningham
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Abstract

In a recent paper, Liu et al. [Nat. Commun. 6:6726 (2015)] claim to perform the first room temperature entanglement-enhanced phase measurement in a solid-state system. We argue here that this claim is incorrect: their measurement is not enhanced because of the entanglement in their system, but instead the enhancement comes from the fact that the phase shift is applied twice to their state.

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P. A. Knott, W. J. Munro, J. A. Dunningham. 2016-04-22. Correspondence: Enhancing a phase measurement by sequentially probing a solid state system. https://doi.org/10.1038/ncomms11520

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