Exchange-dominated surface spin waves in ferromagnetic and antiferromagnetic films

Theoretical results are presented for the localized surface spin waves in thin magnetic films in the exchange-dominated regime. The method is based on a spin-wave operator and Green-function technique that utilizes special properties of tridiagonal and pentadiagonal matrices, and two applications are described here. One is to study the effects of finite film thickness in coupling the modes localized near the two surfaces of an antiferromagnet with a simple cubic structure for the magnetic ions, and numerical examples are given for ultrathin films. The second application is to consider the surface spin waves in ferromagnetic films with body-centered cubic structure and (111) surfaces. Its relevance to recent experimental data for localized modes in epitaxial W/Ni/W films is discussed. (C) 2000 American Institute of Physics. [S0021-8979(00)26908-9].