Magnetic resonance frequencies in multilayers with biquadratic exchange and non-collinear magnetic ordering

摘要

Magnetic resonance frequencies in a magnetic trialeyr or superlattice are theoretically studied. Biquadratic exchange between layers is assumed to be sufficiently strong ofr non-collinear (canted) magnetic ordering to exist in the multilayer. The optic mode freuqency turns out to vanish at the boundary between antiferromagnetic and canted states. It is shown that in the case of longitudinal pumping one can observe the resonance at two different values of magnetic field strength.