Deviation from Matthiessen's Rule in Electron-Irradiated Copper.

摘要

Deviations from Matthiessen's rule (which states that the electrical-resistivity contributions of two different types of scatterers in a metal are additive) occur generally. This paper concerns itself with the deviations arising from relatively simple scatters: by point defects (vacancies and interstitials) created major experimenal feature of the work. Deviations from Matthiessen's rule in pure copper were studied over as wide a temperature range as possible, commensurate with the irradiation and annealing schedule used. In particluar, the deviations were studied as effected by recovery in the first three major defect annealing stages. When analyzing effects due to stageI annealing, damage was produced by irradiation at 4 K; in stages II and III, damage was produced at 4 and at 80 K. In all cases, the electron energy was 1.5 MeV. The deviations were analyzed by considering two deviation-roducing mechanisms: the 'two-band' model and changes in the temperature-dependent part of the electrical resistivity. At low temperatures (below 35 K) the two-band form explains the data when separate temperature dependences for scattering of neck and belly electrons are taken into account. Contributions due to changes in the temperature-dependent part of the electrical resistivity appeared to play no substantial part.