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arXiv · 1405.5275

Surface twist instabilities and skyrmion states in chiral ferromagnets

S. A. Meynell·M. N. Wilson·H. Fritzsche·A. N. Bogdanov·T. L. Monchesky
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Abstract

In epitaxial MnSi/Si(111) films, the in-plane magnetization saturation is never reached due to the formation of specific surface chiral modulations with the propagation direction perpendicular to the film surfaces [Wilson et al. Phys. Rev. B 88, 214420 (2013)]. In this paper we show that the occurrence of such chiral surface twists is a general effect attributed to all bulk and con- fined magnetic crystals lacking inversion symmetry. We present experimental investigations of this phenomenon in nanolayers of MnSi/Si(111) supported by detailed theoretical analysis within the standard phenomenological model. In magnetic nanolayers with intrinsic or induced chirality, such surface induced instabilities become sizeable effects and play a crucial role in the formation of skyrmion lattices and other nontrivial chiral modulations.

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S. A. Meynell, M. N. Wilson, H. Fritzsche, A. N. Bogdanov, T. L. Monchesky. 2014-05-21. Surface twist instabilities and skyrmion states in chiral ferromagnets. https://doi.org/10.1103/physrevb.90.014406

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