Magneto transport and critical behavior in metastable Fe₁₅Cu₈₅

Fe_xCu_100-x binary alloys attracted much attention owing to their rich magnetic phase diagram and the challenges of achieving single phases in these systems. Despite early efforts put toward studying the physical properties of low-Cu doping in Fe–Cu alloys, a detailed understanding of the magnetic, structural and electrical properties of high Cu doping in Fe–Cu alloys remains not clear. In this report, we use X-ray diffraction (XRD), scanning electron microscopy, electrical transport and magnetic measurements to gain more insight into Fe₁₅Cu₈₅ single-phase alloy system. Experimental findings show that the samples exhibit a second-order phase transition, which is consistent with the classical mean-field model. Moreover, negative magnetoresistance is observed at all temperatures and explained through classical models.