Probing the Pinning Strength of Magnetic Vortex Cores with sub-nm Resolution
Christian Holl, Marvin Knol, Marco Pratzer, Jonathan Chico, Imara Lima Fernandes, Samir Lounis, Markus Morgenstern
Received Date: 21st January 20
Understanding the interaction of magnetic textures with defects is crucial to enable applications such as racetrack memories or microwave generators. The interactions appear on the few nm scale, where imaging has not yet been achieved while exerting controlled forces with respect to the defect. Here, we establish a method to determine interactions on the nm and meV scale by employing spin-polarized scanning tunneling microscopy in 3D magnetic field. We track a magnetic vortex core that is pushed by the forces of the 3D field discovering that the core (~104 Fe-atoms) gets successively pinned close to single defects. Reproducing the core path along several defects via parameter fit, we deduce the pinning potential as a mexican hat with short-range repulsive and long-range attractive part. The novel approach to deduce defect induced pinning potentials on the sub-nm scale is transferable to other non-collinear spin textures eventually enabling an atomic scale design of defect configurations, e.g., for guiding or reliable read-out in race-track type devices.
Read in full at arXiv.
This is an abstract of a preprint hosted on an independent third party site. It has not been peer reviewed but is currently under consideration at Nature Communications.