Micromagnetic simulation in two antiferromagnetically coupled ferromagnetic layers separated by a spacer

On the basis of a micromagnetic model, magnetization reversal in two antiferromagnetically coupled ferromagnetic layers (10 nm t(1)/0.9 nmM/t(2) nm films with t(2) = 2, 3, 4, 5 nm, here t(1) and t(2) are the top and bottom layers, respectively, and M the spacer) with the same random anisotropy arrangement can be represented by a computer simulation. The calculation indicates that the appearance of a full antiferromagnetic coupling at remanence requires the antiferromagnetic coupling constant j = -3.5 erg/cm(2) for the 10 nm t(1)/0.9 nmM/3 nm t(2), films and it needs a large j value if t(2) increases for the case of K-u2 = K-u1 = 1 x 10(6) erg/cm(3) and M-s1 = M-s2 = 400 emu/cm(3). H-c follows the equation H-c = -0.755j/M(s)t(1) (j < 0). Why the calculated H-c values deviate from H-c(max) = -j/M(s)t(1) is discussed. (C) 2001 American Institute of Physics.