Specific features of the interaction of microwave radiation with magnetic colloids

Abstract

We study, both experimentally and theoretically, propagation of electromagnetic waves in the microwave range (10.5 GHz) through homogeneous magnetic colloids in a magnetic field. The studies were carried out with partial filling of a rectangular waveguide with tested samples, namely, colloids with magnetite single-domain particles and kerosene as a dispersion medium. The features of the dependences of the transmission coefficient of microwave radiation on the external magnetic field for various volume concentrations of the dispersed phase in the sample are revealed. The model of an ensemble of noninteracting particles was used to interpret the results we obtained. The concentration limits of applicability of the model have been determined.