Collective magnon modes for magnetic dot arrays

• Published in: Journal of magnetism and magnetic materials Vol. 286; pp. 351 - 355
• Main Authors: Galkin, A.Yu, Ivanov, B.A., Zaspel, C.E.
• Format: Journal Article Conference Proceeding
• Language: English
• Published: Amsterdam Elsevier B.V 01-02-2005; Elsevier Science
• Subjects: Condensed matter: electronic structure, electrical, magnetic, and optical properties; Exact sciences and technology; Magnetic properties and materials; Permalloy dots; Physics; Spin waves; Studies of specific magnetic materials; 75.10.Hk; 75.50.Tt; Permalloy dots; Spin waves; 75.30.Ds; Nickel base alloys; 75.50.Tt Permalloy dots; Magnetization; Magnetic field effects; Ferromagnetic materials; Collective mode; Oscillations; Dynamic properties; Dipole interactions; Permalloy; Anisotropy; Square lattices; Magnons; Magnetic properties
• ISSN: 0304-8853
• DOI: 10.1016/j.jmmm.2004.09.092

Both static and dynamic properties of the magnetic dot array with the uniform in-plane magnetization with the most symmetric configuration (round dots placed in a square lattice) have been investigated. Due to the long distance dipole coupling physical properties, such system has a strong four-fold anisotropy with respect both to orientation of the total array magnetization regarding the lattice symmetry axis and to the wave vector direction of a collective oscillations wave. The ferromagnetic state is stable only in the presence of the magnetic field; however, it can also be stable against small perturbations for some orientations of the total magnetization.