Influence of Magnetic Ordering on the Low-Temperature Electrical Resistance of Dilute Cd-Mn and Zn-Mn Alloys

The low-temperature electrical resistivity and superconducting critical temperature of a series of Cd-Mn alloys containing up to 0.38 at.% Mn and the electrical resistivity of a series of Zn-Mn alloys containing up to 0.30 at.% Mn have been measured betwee 0.4 and 30^∘{}K. Resistivity minima and maxima are observed in both alloy systems. The suppression of the critical temperature in Cd-Mn alloys is 44^∘{}K/at.%, which is comparable to that found for the previously investigated Zn systems. Both Cd and Zn alloy systems exhibit a lnT Kondo resistivity term. This term is cut off in the Cd-Mn system by what is believed to be magnetic ordering. The Cd-Mn data are analyzed using Silverstein's theory, where it is deduced that the temperature dependence of the magnetic ordering is governed by a T^-1 behavior. The Zn-Mn alloys exhibit a very broad maximum, and it is believed that magnetic ordering becomes significant at temperatures higher than the resistance maximum. The eventual decrease in resistivity at much lower temperatures is considered a result of spin compensation in the presence of magnetic ordering.