Microwave magnetoelectric fields
  We show that in a source-free subwavelength region of microwave fields there can exist the field structures with local coupling between the time-varying electric and magnetic fields differing from the electric-magnetic coupling in regular-propagating free-space electromagnetic waves. To distinguish such field structures from regular electromagnetic (EM) field structures, we term them as magnetoelectric (ME) fields. We study a structure and conservation laws of microwave ME near fields. We show that there exist sources of microwave ME near fields - the ME particles. These particles are represented by small quasi-2D ferrite disks with the magnetic-dipolar-oscillation spectra. The near fields originated from such particles are characterized by topologically distinctive power-flow vortices, non-zero helicity, and a torsion degree of freedom. Our studies of the microwave ME near fields are combined in two successive papers. In this paper we give a theoretical background of properties of the electric and magnetic fields inside and outside of a ferrite particle with magnetic-dipolar-oscillation spectra resulting in appearance of the microwave ME near fields. Based on the obtained structures of the ME near fields, we discuss effects of so-called ME interactions observed in artificial electromagnetic materials. In the next paper, we represent numerical and experimental studies of the microwave ME near fields and their interactions with matter. 
E.O. Kamenetskii
physics.optics cond-mat.mes-hall cond-mat.mtrl-sci