Special Modes in Spin Wave Spectra of Two-Dimensional Nanodots

S. Mamica Faculty of Physics, A. Mickiewicz University in Poznań, Umultowska 85, 61-614 Poznań, Poland

Full Text PDF

We use a microscopic theory taking into account the nearest-neighbour exchange and dipolar interactions to study two-dimensional magnetic nanodots and nanorings. Magnetic configuration is assumed to form: an in-plane vortex (circular magnetization). We examine the dependence of the frequencies and profiles of spin waves on the dipolar-to-exchange interaction ratio d and the size of the dot (ring). Special attention is paid to some particular modes, including the lowest mode in the spectrum and the fundamental mode, the frequency of which proves almost independent of d. In the case of the lowest mode different profiles are observed: azimuthal, fundamental (quasiuniform) or highly localized, depending on d and the size. We also study the fundamental mode evolution including its hybridization and explain the selection rules.

DOI: 10.12693/APhysPolA.127.365 PACS numbers: 75.30.Ds, 75.70.Kw, 75.75.Jn