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arXiv · 1701.09077

Impact of the skyrmion spin texture on magnetoresistance

Abstract

We investigate the impact of the local spin texture on the differential conductance by scanning tunneling microscopy. In the focus is the previously found non-collinear magnetoresistance, which originates from spin mixing effects upon electron hopping between adjacent sites with canted magnetic moments. In the present work it is studied with lateral resolution both for the zero magnetic field spin spiral state as well as for individual magnetic skyrmions at different magnetic field values. We analyze in detail the response of the differential conductance and find different dependencies of peak energy and peak intensity on the local properties of the non-collinear spin texture. We find that in the center of a skyrmion the peak energy and intensity scale roughly linear with the angle between nearest neighbor moments. Elsewhere in the skyrmion, where the non-collinearity is not isotropic and the magnetization quantization axis varies, the behavior of the peak energy is more complex.

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BibTeXRIS

André Kubetzka, Christian Hanneken, Roland Wiesendanger, Kirsten von Bergmann. 2017-01-31. Impact of the skyrmion spin texture on magnetoresistance. https://doi.org/10.1103/physrevb.95.104433

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