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arXiv · 1601.06922

Edge instabilities and skyrmion creation in magnetic layers

Jan Müller·Achim Rosch·Markus Garst
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Abstract

We study both analytically and numerically the edge of two-dimensional ferromagnets with Dzyaloshinskii-Moriya (DM) interactions, considering both chiral magnets and magnets with interface-induced DM interactions. We show that in the field-polarized ferromagnetic phase magnon states exist which are bound to the edge, and we calculate their spectra within a continuum field theory. Upon lowering an external magnetic field, these bound magnons condense at a finite momentum and the edge becomes locally unstable. Micromagnetic simulations demonstrate that this edge instability triggers the creation of a helical phase which penetrates the field-polarized state within the bulk. A subsequent increase of the magnetic field allows to create skyrmions close to the edge in a controlled manner.

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Jan Müller, Achim Rosch, Markus Garst. 2017-02-13. Edge instabilities and skyrmion creation in magnetic layers. https://doi.org/10.1088/1367-2630%2F18%2F6%2F065006

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