MAGNETIC-STRUCTURE OF TB FILMS AND TB Y SUPERLATTICES/

Thin terbium films and Tb/Y superlattices have been grown by molecular beam epitaxy on sapphire substrates. They have been studied by magnet ization measurements and neutron scattering experiments. Tb directly u ndergoes a transition from the paramagnetic phase to the ferromagnetic one. Neutron scattering experiments performed on superlattices below 220 K show that there is no long range magnetic order except a small t endency to antiferromagnetic coupling between ferromagnetic Tb layers.