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arXiv · 1810.11176

Extreme spin squeezing in the steady state of a generalized Dicke model

Stuart J Masson·Scott Parkins
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Abstract

We present a scheme to generate steady-state atomic spin squeezing in a cavity QED system using cavity-mediated Raman transitions to engineer effective atom-photon interactions, which include both linear and nonlinear (dispersive) atom-cavity couplings, on a potentially equal footing. We focus on a regime where the dispersive coupling is very large and find that the steady state of the system can in fact be a strongly spin-squeezed Dicke state, $|N/2,0\rangle$, of the atomic ensemble. These states offer Heisenberg-limited metrological properties and feature genuine multipartite entanglement among the entire atomic ensemble.

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Stuart J Masson, Scott Parkins. 2018-10-26. Extreme spin squeezing in the steady state of a generalized Dicke model. https://doi.org/10.1103/physreva.99.023822

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