Study of antiferromagnetic coupling by ferromagnetic resonance (FMR)

We have worked out the ferromagnetic resonance (FMR) mode characteristics of an antiferromagnetically coupled two-layer film system. The magnetocrystalline anisotropy was taken to be uniaxial. The analysis predicts the number, positions, intensities and linewidths of the FMR peaks as a function of the coupling strength K. Detailed calculations are given for applied DC magnetic fields either perpendicular to or parallel to the film plane. A 'spin-flop' can occur, there will be a discontinuity in mode position, intensity and linewidth above a critical value of the coupling strength K-crit. (C) 1997 Elsevier Science B.V. All rights reserved.