ELECTRON DOPING EFFECTS ON ELECTRONIC AND MAGNETIC PROPERTIES IN Sr₂FeReO₆

Abstract

We have investigated the electronic and magnetic properties of electron-doped Sr 2−x LaxFeReO 6 (x = 0.0, 0.25, 0.5) using first-principles density functional theory within the generalized gradient approximation (GGA) and GGA + U schemes. Our results reveal that the symmetry of the La-doped compounds is decreased from tetragonal I4/m for perfect sample to monoclinic P 2 1 /n. With increasing La content the absolute magnetic moment of the Re site increases distinctly and the doped electrons are considered to occupy mainly the down-spin Re 5d band from the band calculation. Electronic doping is found to enhance the Curie temperature (Tc) and stabilize the ferromagnetic half-metallic ground states of Sr 2 FeReO 6 . And it is found that the increase of Tc is mainly caused by the increase of ferromagnetic interaction between the Fe-O-Fe.

First-principles study of the structural, electronic, and magnetic properties of double perovskite Sr2FeReO6 containing various imperfections*

“…However, both the saturated magnetic moment and the room-temperature magnetoresistance decrease with increasing La content. Theoretically, the effects of Cr substituting for Fe, [35] La substituting for Sr, [36] and Tc substituting for Re [37] on the structural, electronic, and magnetic properties of Sr 2 FeReO 6 have been investigated by using the first-principles calculations within the density function theory (DFT) framework. Therefore, in this paper, on the point of view of the HM character and magnetization reduction, the structural, electronic, and magnetic properties of the imperfect double perovskite Sr 2 FeReO 6 containing eight different inherent defects of Fe antisite (Fe Re ), Re antisite (Re Fe ), Fe1-Re1 interchange (Fe1-Re1), Fe1-Re4 interchange (Fe1-Re4), Fe vacancy (V Fe ), Re vacancy (V Re ), O vacancy (V O ), and Sr vacancy (V Sr ) are studied by using first-principles projector augmented wave (PAW) within generalized gradient approximation as well as taking into account the on-site Coulomb repulsive interaction (GGA+U).…”