Micromagnetic simulations of magnetization reversal in Co/Ni multilayers

In this paper, the magnetization reversal process of Co/Ni/Co trilayers as studied using finite element micromagnetic simulations. Demagnetization curves were calculated for a multilayer with a Co laver thickness of 5nm and an Ni layer thickness of 15nm. Both the Ni and the Co layer reverse at the same well-defined switching field. A two-step process occurs at interlayer exchange lower than one-third of the bulk value. The transition front a one-step to a two-step reversal process occurs if the anisotropy or Co is considerable high (K-a = 450 kJ/m(3)). A completely different reversal mechanism occurs if the uniaxial anisotropy of the Co layer approaches, 45 kJ/m(3). Now demagnetizing effects override the uniaxial anisotropy, (C) 2001 Elsevier Science B.V. All rights reserved.