Heisenberg scaling with classical long-range correlations

TL;DR

This paper demonstrates that classical long-range correlations in many-body systems can achieve Heisenberg-like precision scaling, challenging the notion that such scaling requires quantum entanglement.

Contribution

It shows how classical correlations in coupled laser networks can produce Heisenberg scaling in parameter estimation, providing a new perspective beyond quantum entanglement.

Findings

Classical long-range correlations can lead to 1/N precision scaling.

Networks of coupled single qubit lasers map onto a classical XY model.

Heisenberg scaling observed in amplitude and phase estimation.

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.