COLLECTIVE EXCITATIONS IN HEISENBERG ULTRATHIN FILMS WITH INHOMOGENEOUS SPATIAL DISTRIBUTION OF MAGNETISATION

R. Łosiński and Z. Onyszkiewicz Magnetism Theory Division, Faculty of Physics A. Mickiewicz University, Umultowska 85, 61-614 Poznań, Poland

Received: July 7, 2000; in final form August 28, 2000

The influence of non-magnetic substrate on the collective excitation of the Heisenberg (s=1/2) ferromagnetic ultrathin films with homogeneous and inhomogeneous spatial distribution of magnetization is investigated. It has been proved that the collective excitation spectrum of ultrathin film may, to a significant degree, depend on the value of the coefficient characterizing the film coupling with its substrate.

PACS numbers: 75.10.Jm, 75.70.-i