On the range of interaction from finite size scaling in magnetic Ni nanowires

A recent experiment reporting a thickness dependence of magnetic properties of Ni nanowires has been re-interpreted in terms of spin-spin interactions eventually ranging beyond nearest neighbors. An analysis following the Ginzburg argument indicated that the system is in the crossover regime from 3D Ising to classical critical behavior as a function of the normalized range of interactions R. The range of the interactions covering three to four coordination spheres of an Ni atom has been found by the fit to literature experimental data on Ni nanowires. Consistency with recent first-principles calculations are discussed.