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arXiv · 1708.09361

Heisenberg scaling with classical long-range correlations

Samuel Fernández-Lorenzo·Jacob A. Dunningham·Diego Porras
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Abstract

The Heisenberg scaling is typically associated with nonclassicality and entanglement. In this work, however, we discuss how classical long-range correlations between lattice sites in many-body systems may lead to a 1/N scaling in precision with the number of probes. In particular, we show that networks of coupled single qubit lasers can be mapped onto a classical XY model, and a Heisenberg scaling with the number of sites appears when estimating the amplitude and phase of a weak periodic driving field.

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Samuel Fernández-Lorenzo, Jacob A. Dunningham, Diego Porras. 2017-08-30. Heisenberg scaling with classical long-range correlations. https://doi.org/10.1103/physreva.97.023843

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