Electronic structure of the DyFe$_{2}$Si$_{2}$ compound: energy band calculations and optical studies

The electronic structure and the optical properties of the DyFe$_{2}$Si$_{2}$ compound have been studied. The calculations of the energy band spectrum taking into account the spin polarization have been performed in an approximation of the local electron density with a correction for strong correlation effects in the 4f shell of a rare-earth metal (the GGA + U method). The optical properties have been studied by the ellipsometric method in a wide range of wavelengths; a number of spectral and electronic characteristics have been determined. It is shown that the optical conductivity of this compound in the region of the interband light absorption is adequately explained in the framework of the performed calculation of electronic states.