Spectral theory of interacting ferrite magnetoelectric particles

The linear magnetoelectric effect provides a special route for local linking magnetic and electric properties. In recently published paper [E. O. Kamenetskii, M. Sigalov, and R. Shavit, J. Appl. Phys. 105, 013537 (2009)], it was shown that no local junctions of the electric and magnetic properties appear from the induced parameters of small electromagnetic scatterers and that point magnetoelectric particles can be realized in quasi-two-dimensional ferrite disks due to the dynamical symmetry breaking effects of the magnetic-dipolar-mode microwave oscillations. These results raise questions about structures of the near fields surrounding magnetoelectric particles and focus our attention on fundamental aspects of interaction between such particles. The fact that for magnetic-dipolar modes in a ferrite disk one has evident quantumlike attributes puts special demands on the methods used for study of interacting magnetoelectric particles. A proper model for coupled particles should be based on the spectral characteristics of the magnetic-dipolar-mode oscillations and an analysis of the overlap integrals for interacting eigenoscillating magnetoelectric elements. In this paper, we present theoretical studies of spectral properties of laterally coupled magnetoelectric ferrite-disk particles. We show that there exists the "exchange" mechanism of interaction between the particles, which is distinctive from the magnetostatic interaction between classical magnetic dipoles and the electromagnetic interaction between small electromagnetic scatterers. The spectral method of interacting magnetoelectric particles proposed in this paper underlies the theory of "magnetoelectric molecules" and furthers realization of dense microwave magnetoelectric composites.