Dominance of magnetic scattering in the electrical-transport of Al70.5Pd22Mn7.5 icosahedral quasicrystal

Conductivity vs. temperature (σ–T) at zero and 8-T field, magneto-resistance (Δρ/ρ), magnetization vs. temperature (M–T) and magnetization vs. field (M–H) of Al70.5Pd22Mn7.5 quasicrystal have been studied in the temperature range of 1.4 K to 300 K. The σ–T variations in both the field conditions show a σ–T minima. In addition to this the σ–T variation at 8 T shows a maxima also at ∼6 K. Comparative analysis shows that the observed σ–T minima arises due to competing inelastic scattering events in the presence of weak-localization effect. These events are e–ph scattering in the dirty-metallic limit (τi ∝ T−2), and the Kondo-type spin-flip scattering (τsf). The maxima observed for the σ–T variation at 8 T, has been attributed to suppression of the spin-flip scattering in the presence of field. The magneto-resistance is found to be large and positive. It was properly accounted only when the Stoner-enhancement, found in the case of spin fluctuating systems, was taken into consideration.