Exchange coupling in magnetic multilayers grown on iron whiskers

Meaningful tests of theoretical predictions of magnetic multilayer properties require the fabrication of multilayers with nearly the same atomic scale precision as the theoretical models. Multilayers grown epitaxially on single-crystal Fe whisker substrates come very close to this ideal standard. We have investigated the growth, magnetic structure, and exchange coupling of Fe/(Ag, Au, Cr, Mn, V, Cu, or Al)/Fe (1 1 0) whisker structures primarily using reflection high-energy electron diffraction (RHEED) and scanning electron microscopy with polarization analysis (SEMPA), and in some systems, confocal magneto-optic Kerr effect (MOKE) microscopy. In cases of nearly layer-by-layer growth, the measured oscillatory coupling periods and strengths agree well with theoretical predictions. For rougher growth, less predictable non-collinear coupling is generally observed.