Critical behavior of electrical resistivity in amorphous Fe-Zr alloys

Electrical resistivity (rho) of the amorphous (a-)Fe100-cZrc (c = 8.5, 9.5 and 10) alloys has been measured in the temperature range 77 to 300 K, which embraces the second-order magnetic phase transition at the Curie temperature point T-c. Analysis of the resistivity data particularly in the critical region reveals that these systems have a much wider range of critical region compared to other crystalline ferromagnetic materials. The value of T-c and specific heat critical exponent, alpha has the same values as those determined from our earlier magnetic measurements. The value of alpha for all the present investigated alloys are in close agreement with the values predicted for three-dimensional (3D) Heisenberg ferromagnet systems, which gives contradiction to the earlier results on similar alloys. It is observed from the analysis that the presence of quenched disorder does not have any influence on critical behavior.