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arXiv · 0906.2322

Six-fold configurational anisotropy and magnetic reversal in nanoscale Permalloy triangles

Laura Thevenard·Dorothee Petit·Huang T. Zeng·Russell P. Cowburn
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Abstract

Six-fold configurational anisotropy was studied in Permalloy triangles, in which the shape symmetry order yields two energetically non-degenerate micromagnetic configurations of the spins, the so-called "Y" and "buckle" states. A twelve pointed switching astroid was measured using magneto-optical experiments and successfully reproduced numerically, with different polar quadrants identified as specific magnetic transitions, thereby giving a comprehensive view of the magnetic reversal in these structures. A detailed analysis highlighted the necessity to include the physical rounding of the structures in the simulations to account for the instability of the Y state.

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Laura Thevenard, Dorothee Petit, Huang T. Zeng, Russell P. Cowburn. 2009-06-12. Six-fold configurational anisotropy and magnetic reversal in nanoscale Permalloy triangles. https://doi.org/10.1063/1.3223311

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