Berlin 2018 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe
O: Fachverband Oberflächenphysik
O 98: Electronic structure: Surface magnetism and spin phenomena I
O 98.9: Vortrag
Donnerstag, 15. März 2018, 17:15–17:30, MA 042
Magnetic Vortex Core Pinning at Atomic Scale Surface Perturbations — •Christian Holl1, Marvin Knol1, Marco Pratzer1, Imara L. Fernandes2, Jonathan Chico2, Samir Lounis2, and Markus Morgenstern1 — 1II. Physikalisches Institut B, RWTH Aachen University and JARA-FIT, Germany — 2Peter Grünberg Institut and Institute for Advanced Simulation, Forschungszentrum Jülich & JARA, D-52428 Jülich, Germany
Spin polarized scanning tunneling microscopy is used to observe magnetic pinning centers in sub micrometer sized iron platelets. The magnetic ground state of these platelets is a flux closed magnetic vortex whose core can be moved laterally by in-plane magnetic fields[1]. Despite their small volume compared to the vortex core, we show that the core pins to the individual surface adsorbates, presumably oxygen, if the core is squeezed by a perpendicular magnetic field of 1.5 T. Comparison with micro-magnetic simulations reveal a pinning energy of up to 250 meV induced by a single adsorbate. Ab initio based calculations show that oxygen adatoms induce anisotropic exchange interactions in the neighbouring substrate atoms[2], which explains the non-concentric pinning position of the core.
A. Wachowiak et al., Science 298, 577-580 (2002)
Funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (ERC-consolidator grant 681405 - DYNASORE).