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arXiv · 2304.02050

Criticality-enhanced Electric Field Gradient Sensor with Single Trapped Ions

Theodoros Ilias·Dayou Yang·Susana F. Huelga·Martin B. Plenio
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Abstract

We propose and analyze a driven-dissipative quantum sensor that is continuously monitored close to a dissipative critical point. The sensor relies on the critical open Rabi model with the spin and phonon degrees of freedom of a single trapped ion to achieve criticality-enhanced sensitivity. Effective continuous monitoring of the sensor is realized via a co-trapped ancilla ion that switches between dark and bright internal states conditioned on a `jump' of the phonon population which, remarkably, achieves nearly perfect phonon counting despite a low photon collection efficiency. By exploiting both dissipative criticality and efficient continuous readout, the sensor device achieves highly precise sensing of oscillating electric field gradients at a criticality-enhanced precision scaling beyond the standard quantum limit, which we demonstrate is robust to the experimental imperfections in real-world applications.

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Theodoros Ilias, Dayou Yang, Susana F. Huelga, Martin B. Plenio. 2023-04-04. Criticality-enhanced Electric Field Gradient Sensor with Single Trapped Ions. https://doi.org/10.1038/s41534-024-00833-w

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