  The electrical resistivity, anisotropic magnetoresistance (AMR), and
anomalous Hall effect of ferromagnetic Mn5Ge3, Mn5Ge3C0.8, and Mn5Si3C0.8 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 Mn5Si3C0.8 the normal Hall
coefficient R0 and the AMR ratio are independent of temperature, these
parameters strongly increase with temperature for the germanide films. This
difference is attributed to the different hybridization of electronic states in
the materials due different lattice parameters and different atomic
configurations (Ge vs. Si metalloid). The concomitant sign change of R0 and the
AMR ratio with temperature observed for the germanide films is discussed in a
two-current model indicating an electron-like minority-spin transport at low
temperatures.
