UNIVERSAL COLLECTIVE EFFECT IN THE LOW-TEMPERATURE RESISTIVITY OF CONCENTRATED AMORPHOUS SPIN-GLASSES

The linear upturn of the electrical resistivity, DELTArho = -C1T, firs t reported below the freezing temperature T(f) of Fe2.4Ni77.6Si8B12, i s shown to be a rather universal feature of metallic glasses containin g localized 3d and 4f moments in a wide range of concentrations. The n ormalized amplitudes, C1T(f), are almost independent of composition an d the magnetoresistance also indicates that impurity scattering of the conduction electrons is not effective below T(f). We discuss these re sults by assuming that the spin-glass order parameter q approximately (1 - T/T(f)) increases the resistivity structure factor of the amorpho us matrix.