The electrical resistivity, anisotropic magnetoresistance (AMR), and anomalous Hall effect of ferromagnetic ${\mathrm{Mn}}_5{\mathrm{Ge}}_3,{\mathrm{Mn}}_5{\mathrm{Ge}}_3{\mathrm{C}}_{0.8}$, and ${\mathrm{Mn}}_5{\mathrm{Si}}_3{\mathrm{C}}_{0.8}$ thin films has been investigated. The data show a behavior characteristic for a ferromagnetic metal, with a linear increase of the anomalous Hall coefficient with Curie temperature. While for ferromagnetic ${\mathrm{Mn}}_5{\mathrm{Si}}_3{\mathrm{C}}_{0.8}$ the normal Hall coefficient $R_0$ and the AMR ratio are independent of temperature, these parameters strongly increase with temperature for ${\mathrm{Mn}}_5{\mathrm{Ge}}_3{\mathrm{C}}_x$ films. This difference is presumably due to the different lattice parameters and different atomic configurations of the metalloids Ge and Si affecting the electronic band structure. The concomitant sign change of $R_0$ and the AMR ratio with temperature observed for ${\mathrm{Mn}}_5{\mathrm{Ge}}_3{\mathrm{C}}_x$ films is discussed in a two-current model indicating an electronlike minority-spin transport at low temperatures.

• Received 5 June 2014
• Revised 12 September 2014

DOI:https://doi.org/10.1103/PhysRevB.90.104421