Dependence of electrical resistivity and magnetoresistance on long-range (F-type) ordering in Zn–Mg–Ho icosahedral quasicrystals

Electrical resistivity and magnetoresistance were measured in Zn60Mg30Ho10 icosahedral quasicrystals annealed at various temperatures that have different degrees of long-range F-type ordering. In the temperature dependence of the electrical resistivity, the sample annealed at 832 K (higher annealing temperature) exhibits a broad maximum at 125 K, which can be interpreted on the basis of the weak localization theory under strong spin-orbit effect. On the other hand, the samples annealed at lower temperatures have negative temperature coefficients of the resistivity in the whole temperature region between 2 K and room temperature. In the case of magnetoresistance, a gradient of magnetoresistance above 40 kOe changes from negative to positive at low temperatures as annealing temperature is raised. Our present results indicate that the long-range F-type ordering systematically affects the behavior of electrical resistivity and magnetoresistance in the Zn60Mg30Ho10 icosahedral quasicrystal.