Electrical Resistance in Superconducting Amorphous Alloy Zr₇₀Ir₃₀

Abstract

Results for the electrical resistance of the superconducting amorphous alloy Zr₇₀Ir₃₀ (ρ=300 μΩ·cm and T_c=3.67 K) are reported. The resistance increases by amount of 3.7% on cooling from 300 K down to 10 K where it shows a hump, and then decreases rapidly approaching to T_c. Above 27 K any magnetoresistance (MR) is not detected, but, in 1.7 K≤T≤27 K, the positive MR is observed and becomes saturated above H_s=12–13 T. The saturated resistance in H≥H_s is greatly enhanced on cooling with a singular dependence, −log T. The paraconductivity near T_c due to the superconducting fluctuation is explained by the Aslamasov-Larkin term, indicating an absence of the Maki-Thompson mechanism.