THE SCATTERING OF ELECTRONS BY EDGE DISLOCATIONS IN AL

A new scheme is proposed to describe the scattering of electrons by deformations due to lattice defects. It is based on the assumption that these deformations are quite homogeneous on an atomic scale with the consequence that the potential seen by the electrons is quite similar to that obtained from self-consistent band-structure calculations for homogeneously deformed lattices. As a first example the scattering by the dilatation field of an edge dislocation is treated. The electrical resistivity is evaluated by solving the Boltzmann equation, taking into account the shape of the Fermi surface and the anisotropy of the scattering probability. Experimental and theoretical values of the electrical resistivity due to edge dislocations in Al are found to be in qualitative agreement showing that the scattering by the dilatation is the dominant mechanism in the case of edge dislocations. As was stated by Watts we find the anisotropy relation rho(perpendicular-to)/rho(parallel-to) < 1.5. That means that edge dislocations have a non-zero component of electrical resistivity rho(parallel-to) along the dislocation line.