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arXiv · 2504.20750

Limits of absolute vector magnetometry with NV centers in diamond

Dennis Lönard·Isabel Cardoso Barbosa·Stefan Johansson·Jonas Gutsche·Artur Widera
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Abstract

The nitrogen-vacancy (NV) center in diamond has become a widely used platform for quantum sensing. The four NV axes in mono-crystalline diamond specifically allow for vector magnetometry, with magnetic-field sensitivities reaching down to $\mathrm{fT}/ \sqrt{\mathrm{Hz}}$. The current literature primarily focuses on improving the precision of NV-based magnetometers. Here, we study the experimental accuracy of determining the magnetic field from measured spin-resonance frequencies via solving the NV Hamiltonian. We derive exact, analytical, and fast-to-compute formulas for calculating resonance frequencies from a known magnetic-field vector, and vice versa, formulas for calculating the magnetic-field vector from measured resonance frequencies. Additionally, the accuracy of often-used approximations is assessed. Finally, we promote using the Voigt profile as a fit model to determine the linewidth of measured resonances accurately. An open-source Python package accompanies our analysis.

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Dennis Lönard, Isabel Cardoso Barbosa, Stefan Johansson, Jonas Gutsche, Artur Widera. 2025-04-29. Limits of absolute vector magnetometry with NV centers in diamond. https://arxiv.org/abs/2504.20750

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