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arXiv · 2003.03345

Heisenberg-limited spin-squeezing via bosonic parametric driving

Peter Groszkowski·Hoi-Kwan Lau·C. Leroux·L. C. G. Govia·A. A. Clerk
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Abstract

Spin-spin interactions generated by a detuned cavity are a standard mechanism for generating highly entangled spin squeezed states. We show here how introducing a weak detuned parametric (two-photon) drive on the cavity provides a powerful means for controlling the form of the induced interactions. Without a drive, the induced interactions cannot generate Heisenberg-limited spin squeezing, but a weak optimized drive gives rise to an ideal two-axis twist interaction and Heisenberg-limited squeezing. Parametric driving is also advantageous in regimes limited by dissipation, and enables an alternate adiabatic scheme which can prepare optimally squeezed, Dicke-like states. Our scheme is compatible with a number of platforms, including solid-state systems where spin ensembles are coupled to superconducting quantum circuits or mechanical modes.

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Peter Groszkowski, Hoi-Kwan Lau, C. Leroux, L. C. G. Govia, A. A. Clerk. 2020-03-06. Heisenberg-limited spin-squeezing via bosonic parametric driving. https://doi.org/10.1103/physrevlett.125.203601

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