Ferromagnetic to Ferromagnetic Transition in the Itinerant Electron Magnet (Sc_0.35Ti_0.65)Fe₂

Abstract

(Sc_0.35Ti_0.65)Fe₂ having the hexagonal Laves phase structure is a ferromagnet with the Curie temperature of 360 K. The ferromagnetic moment changes from 1.3 to 0.9 μ_B around 70 K with increasing temperature. The transition is of the first order. The longitudinal stiffness constant for spin fluctuations changes around 500 K. The magnetic state below 70 K seems to be the same state as that above 500 K and is more localized than the state between 70 and 500 K. The changes of the ferromagnetic moment and the longitudinal stiffness constant are explained as transitions between the two states with the different temperature variation of the local amplitude of spin fluctuations.