Regularities and features in the behavior of electrical and magnetic properties of Co$_2$FeZ (Z = Al, Si, Ga, Ge, Sn, Sb) half-metallic ferromagnetic Heusler alloys

Abstract

The electrical resistivity, magnetization, and Hall effect in Co$_2$FeZ (Z = Al, Si, Ga, Ge, Sn, Sb) ferromagnetic Heusler alloys are studied. A number of correlations between the electronic and magnetic characteristics of the studied alloys are revealed while the atomic number of the Z-component changes. For the Co$_2$FeAl and Co$_2$FeSi half-metallic ferromagnets, the magnitude of magnetization is consistent with the Slater-Pauling rule. For the Co$_2$FeAl, Co$_2$FeSi, and Co$_2$FeGe compounds, a quadratic temperature dependence of electrical resistivity at temperatures below 30 K and above 65 K is found. At the same time, in the region of intermediate temperatures (from 40 K to 65 K), a power-law dependence of $T^b$ with an exponent of 3.5 < b < 4 is observed, which may be due to two-magnon scattering processes.