Magnetic and electrical properties of Ho<inf>0.85</inf>Tb <inf>0.15</inf>Fe<inf>2-x</inf>Mn<inf>x</inf> (0, 0.5, 1.0, 1.5)

The structural, magnetic and electrical properties of Ho 0.85Tb0.15Fe2Mnx (x = 0-0.15) have been characterized through X-ray diffraction, Curie temperature and electrical resistivity measurements. All the alloys are found to crystallize in C15-type cubic Laves phase structure. It is observed that the lattice parameter increases with increasing Mn concentration. The Curie temperature is found to decrease with increasing x, which is attributed to the net decrease in the exchange splitting of the spin-up and spin-down bands. All the materials are seen to exhibit metallic behavior with a decrease in the slope of ρ versus T curve near the Curie temperature. The resistivity behavior is explained on the basis of s-d scattering mechanism and electron-phonon interaction. Spin fluctuations have been observed through Curie temperature and resistivity measurements. © 2003 Elsevier B.V. All rights reserved.