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arXiv · 2601.13413

High Field Diamond Magnetometry Towards Tokamak Diagnostics

S. M. Graham·C. J. Stephen·A. J. Newman·A. M. Edmonds·M. L. Markham·G. W. Morley
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Abstract

Nitrogen vacancy centres (NVC) in diamond have been widely used for near-dc magnetometry. The intrinsic properties of diamonds make them potential candidates for tokamak fusion power diagnostics, where radiation-hard magnetometers will be essential for efficient control. An NVC magnetometer placed in a tokamak will need to operate within a $\geq$ 1 T magnetic field. In this work, we demonstrate fibre-coupled ensemble NVC optically detected magnetic resonance (ODMR) and magnetometry measurements at magnetic fields up to 1.2 T. Sensitivities of approximately 240 to 600 nT/$\sqrt{\textrm{Hz}}$ and 110 nT/$\sqrt{\textrm{Hz}}$ are achieved in a (10-150) Hz frequency range, for non-degenerate and near-$\langle$111$\rangle$ field alignments respectively.

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S. M. Graham, C. J. Stephen, A. J. Newman, A. M. Edmonds, M. L. Markham, G. W. Morley. 2026-01-19. High Field Diamond Magnetometry Towards Tokamak Diagnostics. https://arxiv.org/abs/2601.13413

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