Electrical resistivity and Hall resistivity of thin films of amorphous Cr_1-xMn_xGe

The electrical resistivity rho and the Hall resistivity rho _H of thin films of amorphous Cr_1-xMn_xGe(0<or=x<or=0.9) prepared by the flash-evaporation method are measured in the temperature ranges 4.2-320 and 77-270K, respectively. The temperature coefficient of the electrical resistivity is negative at temperatures between 4.2 and 320K for x>or=0.2 although minima and maxima in the electrical resistivity are observed for x=0 and 0.1. The low-temperature data on the relative electrical resistivity rho _R(t) for x>or=0.3 satisfy the relation rho _R(T)=A+B exp(-CT). The coefficient C shows a minimum at x approximately=0.5. The Hall resistivity increases monotonically with increasing Mn content. A possible explanation for the magnetic properties of amorphous Cr_1-xMn _xGe alloys is given on the basis of these transport measurements.