Influence of Crystal Structure and 3d Impurities on the Electronic Structure of the Topological Material Cd3As2

Abstract

This paper presents a theoretical study of the effects of crystal structure and Mn and Co substitutions for Cd on the electronic structure of the topological material Cd₃As₂. We have carried out density functional theory calculations of the band structure and density of states in tetragonal and cubic Cd₃As₂, as well as in Cd_{3 –x}Mn_xAs₂ and Cd_{3 –x}Co_xAs₂ crystals. The results indicate that the band structure of the cubic Cd₃As₂ phase differs significantly from that of a Dirac semimetal, characteristic of the tetragonal phase. It has also been shown that, after Co substitution for 1/24 of the Cd atoms, the structure of the density of 3d electron states is similar to that of the density of states in the magnetic semiconductor Cd_{3 –x}Mn_xAs₂, with a characteristic minimum at the Fermi energy. At the same time, in the case of analogous Mn substitution for Cd, the density of d-electron states has no such minimum.