Departure from Mathiessen’s rule in dilute cadmium alloys within the 2–14 °K temperature range
Аннотация
Within the 2−11 °K temperature range, where Bloch’s law ρ(T) = AT5 holds true for pure cadmium (with δ0 = 1.5 × 10−5), a study has been made concerning the effect of small quantities (≤0.1%) of Cu, Ag, Au, Zn, Hg, In, and T1 impurities on the coefficient A. This law holds true for alloys at temperatures T ≤ 6°K, where A ∼ log ρ0 and depends on the kind of impurity. The kind of impurity affects this coefficient to the extent that it affects ρ0 and, moreover, the effect of mechanical deformation is similar to that of an impurity, while the magnitude of A does not depend on the dimensional effect. The results obtained here are interpreted qualitatively in the light of the Kagan-Zhernov theory. It is established that the temperature Tres at which the resistivity of an alloy may be considered equal to its residual resistivity ρ0 depends only on the magnitude of ρ0 and does not depend on the kind of impurity and on the size of the specimen.