Brillouin light scattering and ferromagnetic resonance in trilayers with bilinear and biquadratic exchange coupling

We calculate the low-wave-number spin-wave dispersion relations for a trilayer system consisting of two ferromagnetic single-crystal films separated by a nonmagnetic spacer layer, coupled through bilinear and biquadratic exchange interactions, with an applied external field in the plane. The results are successfully applied to interpret Brillouin light scattering and ferromagnetic resonance in epitaxial sputtered (1 0 0)Fe/Cr/Fe trilayers. © 1998 Elsevier Science B.V. All rights reserved.