Der Einfluß der Dipolwechselwirkung auf die Magnetisierung dünner ferromagnetischer Schichten

The magnetization of thin films is calculated for low temperatures, taking into account the exchange interaction, an external magnetic field, and the dipole interaction. The calculations are performed within a quantized phenomenological spin wave theory. For thin enough films, within the temperature range considered, only the lowest spin wave band contributes to the decrease of the magnetization. The influence of the dipole interaction is as follows: The magnetization decreases less rapidly with growing temperature than predicted by calculations within the Heisenberg model; the decrease depends considerably on the angle between the magnetization and the film plane; even atT=0K there is a small increase of the magnetization with growing external field.