STRUCTURAL AND SPIN-WAVE RESONANCE STUDIES OF POLYCRYSTALLINE AND EPITAXIAL PERMALLOY-CHROMIUM LAYERED STRUCTURES

Two sets of magnetic multilayers consisting of two 600 angstrom permal loy (Ni83Fe17) filMS separated by varying thicknesses of Cr, sandwiche d between two further layers of Cr have been studied by spin wave reso nance (SWR). One series of samples consists of crystalline layers depo sited on GaAs (100) with a silver (100) buffer layer to promote epitax ial growth of Cr (100). The permalloy layers display a four-domain (01 1) structure which is deduced from RHEED and symmetry arguments. The s econd series of samples has polycrystalline layers deposited onto glas s substrates. The magnetic coupling of these samples show the role of interfacial roughness at the interior boundaries of the magnetic layer s to be of importance. The epitaxial samples show evidence of oscillat ory exchange coupling, whereas the polycrystalline structures shows no clear sign of such behaviour.