Dipole-exchange spin waves in a periodically layered ferromagnetic nanotube

• Published in: Functional Materials
• Date: 2013
• Main Authors: Gorobets, Y.I., Kulish, V.V.
• Format: Article
• Language: English
• Published: НТК «Інститут монокристалів» НАН України 2013
• Subjects: Modeling and simulation
• Online Access: https://nasplib.isofts.kiev.ua/handle/123456789/120120
• Journal Title: Digital Library of Periodicals of National Academy of Sciences of Ukraine
• Cite this: Dipole-exchange spin waves in a periodically layered ferromagnetic nanotube / Y.I. Gorobets, V.V. Kulish // Functional Materials. — 2013. — Т. 20, № 4. — С. 516-522. — Бібліогр.: 37 назв. — англ.

Spin waves in a periodically layered ferromagnetic nanotube (nanotube magnetophotonic crystal) are investigated. External magnetic field is considered to be applied parallel to the nanotube symmetry axis. The linearized Landau-Lifshitz equation in magnetostatic approximation is used, taking into account the magnetic dipole-dipole interaction, theexchange interaction and the anisotropy effects. As a result, the local dispersion relation (for uniform nanotube sections), the radial wave number spectrum and the longitudinal quasi-wave number spectrum (for the entire nanotube) for spin waves in the above-described nanotube are found. From the radial wave number spectrum, limitations on the transverse-angular modes are defined. The longitudinal quasi-wave number spectrum in the "effective medium" limit is shown to have the same form as for a uniform nanotube (with averaged parameters).