Magnetic Structure of Dy-Co Superlattices near the Compensation Temperature

-The magnetic ordering of a multilayer structure of Dy-Co is studied using complementary methods of polarized neutron reflectometry and Kerr magnetometry. It is found that during the deposition of a layered structure, the Dy and Co layers are partially mixed with the formation of the DyCo2 intermetallic compound. The profiles of the magnetization of individual layers at the atomic level are determined. A description for the noncollinear magnetic structure of the layers near the compensation point using neutron reflectometry data is given. Triple hysteresis loops observed in the same temperature range most likely indicate the nonequivalence of the outer and inner superlattice layers. The inhomogeneity profile of the DyCo2 layer magnetization distribution can be explained by strong exchange interaction at the interfaces. In a small applied magnetic field, the interlayer exchange interaction dominates over the Zeeman energy. The antiparallel ordering of the magnetic moments of the Co and DyCo2 layers is distorted by the magnetic field; as a result, the angle between the magnetization vectors is maximal at the Co/DyCo2 interfaces only.