Ferromagnetic and antiferromagnetic exchange coupling in bcc epitaxial ultrathin Fe(001)/Cu(001)Fe(001) trilayers

Abstract

We have grown a new phase of Cu, bcc Cu, on bcc Fe(001). We have shown that bcc Cu(001) grows epitaxially on bcc Fe(001) and that bcc Fe(001) grows epitaxially on bcc Cu(001). bcc Cu(001) on Fe(001) maintains its structure for 10–11 monolayers before undergoing a structural transition. Ultrathin well-defined trilayers of Fe(001)/Cu(001)/Fe(001) with Cu thicknesses between 6–12 monolayers were grown. Ferromagnetic resonance, Brillouin light scattering, and surface magneto-optical Kerr effect were used to measure the coupling between the Fe layers. The coupling between the Fe layers changed from ferromagnetic to antiferromagnetic between 9–10 monolayers of Cu.