Electric self inductance of quasi-2D magnetic-dipolar-mode ferrite disks

Abstract

An electric current flowing around a loop produces a magnetic field and hence a magnetic flux through the loop. The ratio of the magnetic flux to the electric current is called the (magnetic) self inductance. Can there be a dual situation with a magnetic current flowing around a loop and producing an electric field and hence an electric flux through the loop? Following the classical electrodynamics laws an answer to this question should be negative. Nevertheless special spectral properties of magnetic dipolar modes in a quasi-2D ferrite disk show there are the double-valued-function loop magnetic currents which may produce eigen electric fields and hence eigen electric fluxes through the loop. In this case one can definitely introduce the notion of the electric self inductance as the ratio of the electric flux to the magnetic current. In this paper we show experimentally that in the magnetic-dipolar-mode ferrite disks there exist eigen electric fluxes. These fluxes are very sensitive to permittivity parameters of materials abutting to the ferrite disk. Dielectric samples above a ferrite disk with a higher permittivity than air confine the electric field closely outside the ferrite, thereby changing the loop magnetic currents and thus transforming the magnetic-dipolar-mode oscillating spectrum.