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arXiv · 1604.05030

How to reveal metastable skyrmionic spin structures by spin-polarized scanning tunneling microscopy

Bertrand Dupé·Christian N. Kruse·Tobias Dornheim·Stefan Heinze
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Abstract

We predict the occurrence of metastable skyrmionic spin structures such as antiskyrmions and higher-order skyrmions in ultra-thin transition-metal films at surfaces using Monte Carlo simulations based on a spin Hamiltonian parametrized from density functional theory calculations. We show that such spin structures will appear with a similar contrast in spin-polarized scanning tunneling microscopy (SP-STM) images. Both skyrmions and antiskyrmions display a circular shape for out-of-plane magnetized tips and a two-lobe butterfly contrast for in-plane tips. An unambiguous distinction can be achieved by rotating the tip magnetization direction without requiring the information of all components of the magnetization.

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Bertrand Dupé, Christian N. Kruse, Tobias Dornheim, Stefan Heinze. 2016-04-18. How to reveal metastable skyrmionic spin structures by spin-polarized scanning tunneling microscopy. https://doi.org/10.1088/1367-2630%2F18%2F5%2F055015

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