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arXiv · 2008.13234

An all-optical intrinsic atomic gradiometer with sub-20 fT/cm/$\sqrt{\rm Hz}$ sensitivity in a 22 $\mu$T earth-scale magnetic field

A. R. Perry·M. D. Bulatowicz·M. Larsen·T. G. Walker·R. Wyllie
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Abstract

In this work we demonstrate a high sensitivity atomic gradiometer capable of operation in earth-field level environments. We apply a light-pulse sequence at four times the Larmor frequency to achieve gradiometer sensitivity <20 fT/cm/$\sqrt{\rm Hz}$ at the finite field strength of 22 $\mu$T. The experimental timing sequence can be tuned to the field magnitude of interest. Our one dimensional all-optical gradiometer performs a differential measurement between two regions of a single vapor cell on a 4 cm baseline. Our results pave the way for extensions to operation in higher dimensions, vector sensitivity, and more advanced gradiometers.

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A. R. Perry, M. D. Bulatowicz, M. Larsen, T. G. Walker, R. Wyllie. 2020-08-30. An all-optical intrinsic atomic gradiometer with sub-20 fT/cm/$\sqrt{\rm Hz}$ sensitivity in a 22 $\mu$T earth-scale magnetic field. https://doi.org/10.1364/oe.408486

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