Wide-field magnetometry can be realized by imaging the optically-detected magnetic resonance of diamond nitrogen vacancy (NV) center ensembles. However, NV ensemble inhomogeneities significantly limit the magnetic-field sensitivity of these measurements. We demonstrate a double-double quantum (DDQ) driving technique to facilitate wide-field magnetic imaging of dynamic magnetic fields at a micron scale. DDQ imaging employs four-tone radio frequency pulses to suppress inhomogeneity-induced variations of the NV resonant response. As a proof-of-principle, we use the DDQ technique to image the dc magnetic field produced by individual magnetic-nanoparticles tethered by single DNA molecules to a diamond sensor surface. This demonstrates the efficacy of the diamond NV ensemble system in high-frame-rate magnetic microscopy, as well as single-molecule biophysics applications.
@article{arxiv.2002.06237,
title = {Wide-field dynamic magnetic microscopy using double-double quantum driving of a diamond defect ensemble},
author = {Zeeshawn Kazi and Isaac M. Shelby and Hideyuki Watanabe and Kohei M. Itoh and Vaithiyalingam Shutthanandan and Paul A. Wiggins and Kai-Mei C. Fu},
journal= {arXiv preprint arXiv:2002.06237},
year = {2021}
}