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arXiv · 2002.06237

Wide-field dynamic magnetic microscopy using double-double quantum driving of a diamond defect ensemble

Zeeshawn Kazi·Isaac M. Shelby·Hideyuki Watanabe·Kohei M. Itoh·Vaithiyalingam Shutthanandan·Paul A. Wiggins·Kai-Mei C. Fu
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Abstract

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.

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Zeeshawn Kazi, Isaac M. Shelby, Hideyuki Watanabe, Kohei M. Itoh, Vaithiyalingam Shutthanandan, Paul A. Wiggins, Kai-Mei C. Fu. 2020-02-14. Wide-field dynamic magnetic microscopy using double-double quantum driving of a diamond defect ensemble. https://doi.org/10.1103/physrevapplied.15.054032

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