Residual resistivity dipoles
Abstract
Current flow past lattice defects in metals is associated with a localized conduction band polarization. This has become generally recognized in electromigration theory, but there is disagreement about the details of the polarization pattern. Discussions by others have emphasized polarization terms which are first order in the perturbation potential. This paper analyzes the polarization terms which are proportional to scattering probabilities and thus related to the increase in resistivity. These are second order, or higher, in the scattering potential. A simple physical picture is used to estimate the size of this dipole moment associated with the residual resistivity. A quantum mechanical discussion is given for the one-dimensional case. The conditions under which the polarization can be expected to be linear in the scattering cross-section is discussed. © 1975 Springer-Verlag.