Spectrum of spin waves in a magnonic crystal with a structure defect

Abstract

Problem of the propagation of spin waves in a one-dimensional magnonic crystal with a structure defect has been analyzed theoretically. As a magnonic crystal, we consider a multilayer magnet representing an infinite system of plane-parallel alternate adjacent exchange-coupled slabs of magnets of two types. As a single structure defect that breaks the translational symmetry of the crystal, we consider a layer that is different from the layers composing the magnonic crystal. A dispersion law for spin-wave modes localized at the defect has been obtained. The appearance of several defect modes in the band gap has been analyzed depending on the parameters of the defect layer.