Vortices in two-dimensional nanorings studied by means of the dynamical matrix method

• Veröffentlicht in: Физика низких температур
• Datum: 2015
• ISSN: 0132-6414
• 1. Verfasser: Mamica, S.
• Format: Artikel
• Sprache: Englisch
• Veröffentlicht: Фізико-технічний інститут низьких температур ім. Б.І. Вєркіна НАН України 2015
• Schlagworte: К 80-летию уравнения Ландау–Лифшица
• Online Zugang: https://nasplib.isofts.kiev.ua/handle/123456789/128086
• Назва журналу: Digital Library of Periodicals of National Academy of Sciences of Ukraine
• Zitieren: Vortices in two-dimensional nanorings studied by means of the dynamical matrix method / S. Mamica // Физика низких температур. — 2015. — Т. 41, № 10. — С. 1030–1042. — Бібліогр.: 74 назв. — англ.

This paper concerns an investigation of the spin wave excitations in magnetic nanoparticles. We provide a detailed
 derivation of the theoretical method for the determination of the normal modes of confined magnetic systems
 based on a discrete lattice of magnetic moments. The method is based on the damping-free Landau–Lifshitz
 equation and general enough to be utilized for the magnetic system of any dimensionality, magnetic structure,
 shape, and size. As an example we explore the influence of the competition between exchange and dipolar interactions
 on the spectrum of normal modes as well as on the stability of the vortex state in two-dimensional
 nanorings. We show the lowest-frequency mode to be indicative of the dipolar-to-exchange iterations ratio.
 We also study behavior of the fundamental mode and present the influence of both, the discreteness of the lattice
 and the dipolar-to-exchange iterations ratio, on its hybridization with azimuthal modes. We complete the paper with
 a selective review of the spin wave excitations in circular dots to compare with the results obtained for the rings.