ELECTRON–ELECTRON INTERACTION, QUANTUM INTERFERENCE AND SPIN FLUCTUATION EFFECTS IN THE RESISTIVITY OF Fe-RICH Fe-Zr METALLIC GLASSES

Abstract

Electrical resistivity (ρ) measurements have been performed in various temperature ranges on different batches of samples with nominal composition x = 0 and 1 in the amorphous alloy series Fe 90+x Zr 10-x. An elaborate data analysis brings out clearly the actual functional dependences of ρ on temperature (T) in different temperature ranges. The results of this analysis, when discussed in the light of existing theories, permit identification of the dominant mechanisms of electrical transport in different temperature regions as electron-diffuson (non-propagating longitudinal spin fluctuations) scattering for T≤10 K, enhanced electron–electron interaction (EEI) effects in the range 10 K ≤T≤25 K and quantum interference (QI) effects, electron–phonon (e–ph) as well as electron–spin fluctuations scattering in different temperature ranges above 25 K. EEI and QI contributions to ρ, in turn, yield fairly accurate values for the diffusion constant (that obey the Einstein relation) and the dephasing time. Out of the inelastic scattering processes such as e–ph scattering, spin–orbit scattering and spin–flip scattering that destroy phase coherence, e–ph scattering seems to be the most effective dephasing mechanism. Dephasing persists to temperatures well above the Curie point and Debye temperature in the amorphous alloys in question.