Quantum corrections and magnetotransport in 3D Dirac semimetal Cd$_{3-x}$Mn$_{x}$As$_{2}$ films

Thin films of solid solutions based on the three-dimensional Dirac semimetal Cd$_3$As$_2$ with the addition of manganese are investigated. Cd$_{3-x}$Mn$_{x}$As$_{2}$ films ($x$ = 0, 0.05, and 0.1) 50–70 nm in thickness are formed on a glassceramic substrate using vacuum-thermal deposition from cadmium arsenide ingots doped by Mn and fabricated by direct alloying elements by the vacuum-cell method. The temperature and magnetic-field dependences of the resistance are measured and the transport parameters of the films under study are determined. Positive magnetoresistance of the characteristic shape corresponding to the contribution of the weak antilocalization effect is observed for films with $x$ = 0 and 0.05. The contribution from the weak localization effect is observed at a higher Mn content ($x$ = 0.1). This change in the quantum correction type as applied to topological semimetals points to reconstruction of the band structure and transition from the Dirac semimetal state into a trivial semiconductor phase, which corresponds to the critical Mn content $x_{c}\sim$ 0.07 in this case.