WALL STRUCTURES IN FERRO ANTIFERROMAGNETIC EXCHANGE-COUPLED BILAYERS - A NUMERICAL MICROMAGNETIC APPROACH

Two-dimensional wall structures in ferro/antiferromagnetically exchang e-coupled bilayers are calculated by means of numerical micromagnetic simulations. Extended wall tails occurring in non-compensated structur es are duly accounted for via the introduction of a variable meshing a long one space direction. Constant charge finite volumes and the appli cation of general boundary conditions in the presence of interlayer ex change coupling and/or surface anisotropy further characterize the com putation scheme. Simulated wall structures in zero field are compared with various approximate analytical models and the ranges of validity of the latter are made explicit. Hard-axis field intrinsic magnetizati on and hysteresis properties are outlined, and a sketch of the wall st ructure phase diagram is proposed for given material parameters and a specific geometry.