Physical properties and electronic structure of YbFe2As2

Abstract We report the structural, magnetic and electronic properties of a new compound YbFe2As2 based on our experimental studies and spin polarized density functional theory (DFT) calculations. X-ray diffraction measurements on the crushed crystals of YbFe2As2 shows monoclinic unit cell structure. Our electronic structure calculations were based on the Perdew-Burke Ernzerhof method (PBE + U) to treat the strong correlation effects between the 3d and 4f electrons of the Fe and Yb atoms respectively. The calculated partial density of states reveal that the hybridization between Yb-4f and Fe-3d states lead to these strong electron-correlation effects, which could provide a plausible explanation for the breaking of a possible antiferromagnetic order into small regions of ferromagnetic correlations contributed by the Fe atoms. This conjecture seems to be in agreement with our magnetization and electrical resistivity results. The density of states (DOS) reveals a metallic behaviour, which is also in agreement with the electrical resistivity measurements. The electronic band structure of YbFe2As2 depicts that in addition to high dispersion bands in the conduction band region, there are flat bands at the Fermi region composed of As-4p states and Fe-3d states.