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arXiv · 2203.14230

DC Quantum Magnetometry Below the Ramsey Limit

Alexander A. Wood·Alastair Stacey·Andy M. Martin
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Abstract

We demonstrate quantum sensing of dc magnetic fields that exceeds the sensitivity of conventional $T_2^\ast$-limited dc magnetometry by more than an order of magnitude. We used nitrogen-vacancy centers in a diamond rotating at periods comparable to the spin coherence time, and characterize the dependence of magnetic sensitivity on measurement time and rotation speed. Our method up-converts only the dc field of interest and preserves the quantum coherence of the sensor. These results definitively improve the sensitivity of a quantum magnetometer to dc fields, an important and useful addition to the quantum sensing toolbox.

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Alexander A. Wood, Alastair Stacey, Andy M. Martin. 2022-03-27. DC Quantum Magnetometry Below the Ramsey Limit. https://doi.org/10.1103/physrevapplied.18.054019

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