Nonlinear effects in corundum and ilmenite in high frequency electromagnetic fields.

This paper details the results of a comparative study of two materials having the same structure, but drastically different radiophysical characteristics. Corundum ceramic samples were synthesized from pure substances by firing a charge in air at 1450°C for 1 h. The second material was prepared from natural ilmenite without heat treatment using an epoxy polymer binder. Measurements of the transmission and reflection factors within the frequency range of 8-26 GHz indicate that corundum ceramic samples scatter electromagnetic radiation (EMR) exhibiting a pronounced dispersion of the reflection and transmission factors. On the contrary, ilmenite samples absorb EMR showing no dispersion at all. The differences in the radiophysical characteristics are due to the presence of magnetic impurities in the crystal lattices of corundum and ilmenite and the specific features of the spin-phonon interaction in dielectric and ferrite materials. [ABSTRACT FROM AUTHOR]