Abstract
We present an approach to infer the surface density of magnetic moments in ultrathin ferromagnetic films with perpendicular anisotropy. It relies on quantitative stray-field measurements with an atomic-size magnetometer based on the nitrogen-vacancy center in diamond. The method is applied to microstructures patterned in a 1-nm-thick film of CoFeB. We report measurements of with a few percent uncertainty and a spatial resolution in the range of , an improvement by several orders of magnitude over existing methods. As an example of application, we measure the modifications of induced by local irradiation with ions in an ultrathin ferromagnetic wire. This method offers a route to study variations of magnetic properties at the nanoscale.
- Received 2 March 2015
DOI:https://doi.org/10.1103/PhysRevApplied.4.014003
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