Electrical transport in nanostructured Ni3Al at low temperatures

Abstract

The electrical resistivity in nanostructured Ni₃Al has been discriminated to be dominated fully by the electron-magnon scattering with spin fluctuations and evolve in the form of T ^5/3 and T ^3/2 below and above its Curie temperature. In addition to doping into γ′-Ni₃Al nanophases, excessive Ni atoms are demonstrated to aggregate at the cores of Ni₃Al so that some γ-Ni nanophases are embedded in the γ′-Ni₃Al ones for forming the core/shell nanostructure. The itinerant electrons from γ′-Ni₃Al nanophases is further suggested to wander around the phonons in both γ-Ni and γ′-Ni₃Al nanophases for screening the electron-phonon interactions. Consequently, the conduction electrons are scattered largely by spin fluctuations in γ′-Ni₃Al shells to suppress the contribution of phonons to the electron transport in nanostructured Ni₃Al.