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arXiv · 0911.5121

Macrospin limit and configurational anisotropy in nanoscale Permalloy triangles

Laura Thevenard·Huang Tao Zeng·Dorothée Petit·Russell P. Cowburn
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Abstract

In Permalloy submicron triangles, configurational anisotropy - a higher-order form of shape anisotropy - yields three equivalent easy axes, imposed by the structures' symmetry order. Supported by micromagnetic simulations, an experimental method was devised to evaluate the nanostructure dimensions for which a Stoner-Wohlfarth type of reversal could be used to describe this particular magnetic anisotropy. In this regime, a straightforward procedure using an in-plane rotating field allowed us to quantify experimentally the six-fold anisotropy fields for triangles of different thicknesses and sizes.

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Laura Thevenard, Huang Tao Zeng, Dorothée Petit, Russell P. Cowburn. 2009-11-26. Macrospin limit and configurational anisotropy in nanoscale Permalloy triangles. https://doi.org/10.1016/j.jmmm.2010.01.048

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