Magnetic phase diagram of sigma-phase Fe55Re45 compound in the H-T coordinates

Abstract

In-field DC and AC magnetization measurements were carried out on a sigma-phase Fe55Re45 intermetallic compound aimed at the determination of the magnetic phase diagram in the H-T plane. Field-cooled, MFC, and zero-field-cooled, MZFC, DC magnetization curves were measured in the magnetic field, H, of up to 1200 Oe. AC magnetic susceptibility measurements were carried out at a constant frequency of 1465 Hz under DC fields of up to H = 500 Oe. The obtained results provide evidence for re-entrant magnetism in the investigated sample. The magnetic phase diagrams in the H-T plane have been outlined based on characteristic temperatures determined from the DC and AC measurements. The phase diagrams are similar, yet not identical. The main difference is that, in the DC diagram constructed, there are two crossover transitions within the strong-irreversibility spin-glass state, whereas, in the AC susceptibility based diagram, only one transition is observed. The border lines (irreversibility, crossover) can be described in terms of the power laws.