Macrospin limit and configurational anisotropy in nanoscale permalloy triangles

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.