Residual Resistivity and Kohler's Rule in Nickel

Abstract

Measurements have been made of the magnetoresistance of nickel polycrystalline foils. The specimens have been treated to form particular sets, each of which is thought to contain predominantly one kind of scattering center, e.g., chromium impurity atoms, dislocations, etc. The data from any one set obey Kohler's rule provided the magnetic induction B is the relevant field and the reducing resistivity ρ₀^B is taken as ρ at B=0. A novel extrapolation procedure is described for finding ρ₀^B. The internal field 4πM₈ gives rise to a correction to the residual resistance at zero applied field which for high‐purity samples can be large, comparable to the residual resistance itself.