Transport properties, giant moments and nearly magnetic impurities in some nickel alloys near the magnetic transition

Abstract

The authors present a systematic study of the magnetic transition from the paramagnetic to the ferromagnetic state in some nickel concentrated alloys Ni_cT_1-c (T=V, Cr, Mo, Ru, Cu). The magnetic measurements between 4K and 300K show that this transition occurs from the coupling between giant moments whose concentration increases when the nickel concentration increases up to the critical concentration c_cr; their magnitude is the largest critical composition. A detailed study of NiV, NiMo and NiCu alloys shows that the magnetization results from giant moments whose magnitude increases when c to c_cr and from nearly magnetic impurities in the vicinity of these moments. The existence of this nearly magnetic term is consistent with the temperature dependence of the resistivity in all the investigated alloys and with the magnetoresistance measurements in NiT alloys (T=V, Mo, Cu).