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arXiv · 2311.06055

Comparing continuous and pulsed nitrogen-vacancy DC magnetometry in the optical-power-limited regime

Maggie Wang·Michael Caouette-Mansour·Adrian Solyom·Lilian Childress
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Abstract

Ensembles of nitrogen-vacancy (NV) center spins in diamond offer a robust, precise and accurate magnetic sensor. As their applications move beyond the laboratory, practical considerations including size, complexity, and power consumption become important. Here, we compare two commonly-employed NV magnetometry techniques -- continuous-wave (CW) vs pulsed magnetic resonance -- in a scenario limited by total available optical power. We develop a consistent theoretical model for the magnetic sensitivity of each protocol that incorporates NV photophysics - in particular, including the incomplete spin polarization associated with limited optical power; after comparing the models' behaviour to experiments, we use them to predict the relative DC sensitivity of CW versus pulsed operation for an optical-power-limited, shot-noise-limited NV ensemble magnetometer. We find a $\sim 2-3 \times$ gain in sensitivity for pulsed operation, which is significantly smaller than seen in power-unlimited, single-NV experiments. Our results provide a resource for practical sensor development, informing protocol choice and identifying optimal operation regimes when optical power is constrained.

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Maggie Wang, Michael Caouette-Mansour, Adrian Solyom, Lilian Childress. 2023-11-10. Comparing continuous and pulsed nitrogen-vacancy DC magnetometry in the optical-power-limited regime. https://arxiv.org/abs/2311.06055

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