First-principles Study On A₂FeMoO₆（A=Sr,Ca,Ba） And Optical Properties Of （001） Surface

To study spintronics materials having a high spin polarization is an important research direction in the field of modern condensed matter physics. Since double perovskite oxides A2B’B"O6 has half-metal properties, it has been one of the ideal alternative material devices to study spintronics devices. In this paper, we calculated the electronic structure, magnetic and optical properties of A2 Fe Mo O6(A=Sr,Ca,Ba) and its(001) surface by VASP which is based on the density functional theory and projector augmented wave pseudopotential method, and analyzed the differecses of properties of bulk and its surface. The main contents are as follows:Firstly, we calculated the electronic structures, magnetic performances and optical properties of A2 Fe Mo O6(A=Sr,Ca,Ba) and found all of them have half metallic magnetic.We compared with the existing theories and experiments and found the results were completely suitable. They verified the rationality of calculation methods and structures.Secondly, perovskite solar cells have higher conversion efficiency and lower cost compared with conventional solar cells, so we calculated their dielectric function,reflectivity, refractive index and extinction coefficient, absorption coefficient, energy loss spectroscopy. We also analyzed and compared them.Finally, we calculated the(001) surface of A2 Fe Mo O6(A=Sr,Ca,Ba) and obtained the electronic structure, magnetic performance and optical properties. And we compared the differecses of properties with bulk.