Investigation of microwave optical constants of bulk iron oxides

The paper presents an analysis of microwave optical constants of iron oxides (magnetite and hematite) by means of the Kramers-Kronig method. Spectral reflectivities of magnetite and hematite in a wide frequency range (from extreme ultraviolet to microwave) were derived based on multiple experimental data found in the literature. The obtained dependencies were used to calculate optical constants of the minerals at 12-145 GHz and compare the results with other reported theoretical and laboratory studies.