The electronic and magnetic properties of transition-metal element doped three-dimensional topological Dirac semimetal in Cd3As2

Abstract

A three-dimensional (3D) topological Dirac semimetal (TDSM) Cd₃As₂ has very recently been discovered, which can be turned into a variety of quantum phases by breaking either time reversal symmetry or inversion symmetry. Here, we present a density functional theory (DFT) study to systematically investigate the doping effects of 3d transition-metal (TM) atoms (Ti:Cu) in Cd₃As₂. The results reveal that the introduced 3d TMs lower the symmetries of the system, resulting in massive Dirac fermions with gap opening at the Dirac point. The substitution of Cr atoms could tailor Cd₃As₂ to a ferromagnetic half-metal due to the effective p–d exchange. The Monte Carlo simulations predict that the Curie temperature (T_c) of Cr–Cd₃As₂ is up to room temperature, suggesting powerful potential for further spintronic applications.