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arXiv · 2204.13684

Force-Gradient Sensing and Entanglement via Feedback Cooling of Interacting Nanoparticles

Henning Rudolph·Uroš Delić·Markus Aspelmeyer·Klaus Hornberger·Benjamin A. Stickler
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Abstract

We show theoretically that feedback-cooling of two levitated, interacting nanoparticles enables differential sensing of forces and the observation of stationary entanglement. The feedback drives the two particles into a stationary, non-thermal state which is susceptible to inhomogeneous force fields and which exhibits entanglement for sufficiently strong inter-particle couplings. We predict that force-gradient sensing at the zepto-Newton per micron range is feasible and that entanglement due to the Coulomb interaction between charged particles can be realistically observed in state-of-the-art setups.

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Henning Rudolph, Uroš Delić, Markus Aspelmeyer, Klaus Hornberger, Benjamin A. Stickler. 2022-04-28. Force-Gradient Sensing and Entanglement via Feedback Cooling of Interacting Nanoparticles. https://doi.org/10.1103/physrevlett.129.193602

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