Magnetic and thermal properties of Er75Dy25 single crystals

We report on an experimental study of the thermal and magnetic properties of Er75Dy25 single crystals with magnetic fields applied parallel to the [0001] and [101̅ 0] directions. The [0001] direction is the easy axis of magnetization, while the [101̅ 0] direction is the hard axis of magnetization. Three major transitions are observed in the heat capacity, magnetization, and alternating current magnetic susceptibility data. A firstorder transition is observed at ∼30 K, and two second-order transitions occur at ∼45 and ∼110 K. The H-T phase diagrams constructed from the experimental data reveal that several magnetic phases, including ferromagnetic cone, ferromagnetic fan, and c axis–modulated phases, exist in an Er75Dy25 single crystal. Both similarities and dissimilarities are observed in the H-T phase diagrams of Er75Dy25 when compared to the HT phase diagrams of pure Er single crystals.