Electrical dislocation resistivity and anisotropic scattering in high-purity copper single crystals

The experimental dislocation resistivity (or the deviation from Matthiessen's rule (DMR)) at 4.2 and 77 K of several single slip and multislip crystals was investigated. Additionally low-field Hall effect measurements at 4.2K using a dc SQUID picovoltmeter were performed in order to study the anisotropy of electron–dislocation and electron-impurity scattering directly. It is shown that oxygen annealing applied to increase the “electrical purity” of the crystals does not change the character of the scattering behaviour. The anisotropy parameters A_dis for electron–dislocation scattering derived within the two-group model are in good agreement with recent results for high-purity polycrystals.