Spin wave localization in a triangular nanomagnet

Abstract

Brillouin measurements have been carried out on a low density array of 20 nm thick Ni80 Fe20 equilateral triangles with an edge length of 190 nm, under an in-plane magnetic field applied perpendicular to one edge of the triangular magnets. The dynamical matrix method is employed to identify the observed spin wave modes. Most of the observed modes can be classified into different categories based on their mode profiles, with modes in each category characterized by the same number of nodal lines along the direction of the applied field but having different spatial localization. Hybrid modes with different numbers of nodal lines in different regions of the nanomagnet are also found to exist. The spatial localization and the spatial variation in the spin wave character for the observed modes have been calculated based on the spin wave well model. Calculations based on the simple model give reasonable agreement with numerical results obtained by the dynamical matrix method. © 2010 American Institute of Physics.