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arXiv:2112.09004 · Physical Review Applied

Femtotesla Nearly-Quantum-Noise-Limited Pulsed Gradiometer at Earth-Scale Fields

Vito Giovanni Lucivero, Wonjae Lee, Mark E. Limes, Elizabeth L. Foley, Thomas W. Kornack, Michael V. Romalis

Published Aug 12, 2022• 49 citations
arXivHTMLPDF

Abstract

Applications of optical magnetometers in demanding environments require a high common-mode rejection ratio (CMRR) to effectively suppress ambient noise, but challenges still remain to achieve experimental sensitivity at the quantum noise level. The authors develop a compact magnetic gradiometer featuring a high CMRR and a differential sensitivity of tens of femtoteslas over a broad dynamic range, including Earth's field magnitude. This gradiometer is also nearly quantum-noise-limited, which is compatible with quantum enhancement techniques in geomagnetic fields and can be used in unshielded environments such as space science, navigation, and biomedicine.

DOI
10.1103/physrevapplied.18.l021001

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