Resonance Scattering and the Electrical and Thermal Resistivities Associated with Extended Defects in Crystals

Abstract

The general failure of theory to account for the observed electrical and thermal resistivities associated with dislocations is reviewed in the light of the resonance scattering previously shown to be a characteristic property of linear defects in crystals. Expressions for the scattering width and density of states near a resonance are obtained, and the magnitude of the resonance scattering is shown to be consistent with the observed electrical resistivity of dislocations in a number of metals. Observed stacking-fault electrical resistivities are consistent with the absence of resonance scattering; such scattering is not expected to occur for plane defects. The resonance-scattering mechanism is shown to be capable of accounting for the magnitude of the dislocation thermal resistivity in ionic crystals, and also, possibly, for the much smaller effect in metals. The observed temperature dependence of the thermal resistivity in ionic crystals is rather difficult to explain in terms of resonance scattering, although it would probably be expecting too much for the simple treatment given here to deal adequately with this point. The generally encouraging results would appear to justify the expenditure of more effort, both experimentally and theoretically, on these problems.