Sharp-pointed susceptibility of ferromagnetic films with magnetic anisotropy inhomogeneous in thickness

Abstract

It is shown that in ferromagnetic films with anisotropy inhomogeneous in thickness, an interphase boundary can be formed for certain values and directions of the magnetic field. This boundary has a stable magnetic configuration. It is oriented parallel to the film plane and separates the regions with different orientations of the magnetization. In an alternating magnetic field, the interphase boundary oscillates, which may be accompanied by a resonance. The field and frequency dependences of the components of the magnetic susceptibility tensor are determined. It is shown that the susceptibility coefficients at a resonance are extremely sensitive to the direction of the external magnetic field which can underlie the development of a highly sensitive sensor.