No abstract

No abstract

No abstract

No abstract

A microscopic magnetic antiphase domain structure has been observed in a single-crystal Gd-Y superlattice by neutron diffraction. Furthermore, this long-range antiferromagnetic correlation is found to occur in a multibilayer, in which each biiayer consists of A^od ferromagnetic atomic planes of Gd followed by N^ planes of nonmagnetic Y, for NY = NQ^ = 10 but not for A^y == 6 or 20. This oscillatory behavior is consistent with recent theoretical speculation that the Gd moments are coupled through the intervening Y via the Ruderman-Kittel-Kasuya-Yosida interaction.