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arXiv · 1801.04764

Quantum sensing of the phase space displacement parameters using a single trapped ion

Peter A. Ivanov·Nikolay V. Vitanov
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Abstract

We introduce a quantum sensing protocol for detecting the parameters characterizing the phase space displacement by using a single trapped ion as a quantum probe. We show that thanks to the laser-induced coupling between the ion's internal states and the motion mode the estimation of the two conjugated parameters describing the displacement can be efficiently performed by a set of measurements of the atomic state populations. Furthermore, we introduce a three-parameter protocol capable to detect the magnitude, the transverse direction and the phase of the displacement. We characterize the uncertainty of the two- and three-parameter problems in terms of the Fisher information and show that state projective measurement saturates the fundamental quantum Cramer-Rao bound.

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Peter A. Ivanov, Nikolay V. Vitanov. 2018-01-15. Quantum sensing of the phase space displacement parameters using a single trapped ion. https://doi.org/10.1103/physreva.97.032308

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