Scanning magnetometry with nitrogen-vacancy (NV) centers in diamond has emerged as a powerful microscopy for studying weak stray field patterns with nanometer resolution. Due to the internal crystal anisotropy of the spin defect, however, external bias fields -- critical for the study of magnetic materials -- must be applied along specific spatial directions. In particular, the most common diamond probes made from {100}-cut diamond only support fields at an angle of θ=55∘ from the surface normal. In this paper, we report fabrication of scanning diamond probes from {110}-cut diamond where the spin anisotropy axis lies in the scan plane (θ=90∘). We show that these probes retain their sensitivity in large in-plane fields and demonstrate scanning magnetometry of the domain pattern of Co-NiO films in applied fields up to 40 mT. Our work extends scanning NV magnetometry to the important class of materials that require large in-plane fields.
@article{arxiv.2201.06450,
title = {Scanning nitrogen-vacancy center magnetometry in large in-plane magnetic fields},
author = {P. Welter and J. Rhensius and A. Morales and M. S. Wörnle and C. -H. Lambert and G. Puebla-Hellmann and P. Gambardella and C. L. Degen},
journal= {arXiv preprint arXiv:2201.06450},
year = {2022}
}