SPIN CONFIGURATIONS AND SPIN-WAVE EXCITATIONS IN EXCHANGE-COUPLED BILAYERS

The ground-state spin configuration of antiferromagnetically coupled f erromagnetic thin films is determined by competition between anisotrop ies, interlayer exchange, and the applied field. A theory for spin wav es is presented where both exchange and dipolar interactions are accou nted for and it is shown how dramatic changes in the spin-wave frequen cies can be observed by carefully choosing the experimental geometry. Also, many details of the ground-state spin configuration can be obtai ned by studying the behavior of the spin-wave frequencies as functions of propagation direction and applied field strength in these geometri es. The results are summarized from the point of view of possible ligh t-scattering experiments.