Influence of metal-metalloid elements on the electrical resistance of amorphous materials

Abstract

We report systematic studies on the electrical resistivity, ρ, in the amorphous transition metal based alloy series T_1−yG_y, with T = A_1−xB_x (where A,B = Fe, Co, Ni, Cr, Mn) and the metalloid G (=P, B, Si, Al) over the temperature range 20 mK to 300 K. All the alloys studied show a minimum in the resistivity at a characteristic temperature T_min which varies from 8 K to 250 K depending on the system. For a given system the resistivity rise below t_min is found to be a maximum around the critical conc region where the magnetic long‐range order parameter →0. Also, in all the alloys below the resistance minimum it is found that dρ (T)/dT∼–ρ (T) with deviations setting in at lower temperatures. The coefficient of the T² term in ρ above T_min is strongly influenced by the metalloid concentration.