STABILITY, ELECTRONIC AND MAGNETIC PROPERTIES OF DIRAC SEMIMETALL CdAs, DOPED BY MANGANESE AND CHROMIUM

Doping Dirac semimetals by magnetic atoms promises the development of new topological materials with broken time-reversal symmetry. According to the theoretical models, the unusual transport properties should be observed in such materials: negative magnetoresistance, π Aharonov–Bohm effect, quantum Hall effect and other ones. However, the real alloys are complex objects which differ in many ways from model representations. In this paper the stability and properties of two substitutional alloys are analysed by means of the first principles calculations: (CdMn)As and (CdCr)As. The main difference between these two topological alloys is due to the type of doping: isovalent in case of Mn and non-isovalent in case of Cr. Our calculations show that the valence of doped atoms determines directly the position of the Fermi level and the nature of spin ordering in alloys under consideration, as well as the preservation of the Dirac cone in electron spectrum. The features found are of a regular nature and weakly depend on the details of the spatial arrangement of magnetic atoms in alloys.