Magnetization and specific heat study on a SmCuAl3 single crystal

Abstract We report on structural and magnetic properties of a SmCuAl3 single crystal. The sample quality, phase and structure purity were investigated by means of x-ray and neutron diffraction, BSE electron microscopy and EDX analysis. The crystal structure was identified to be of a tetragonal BaNiSn3-type (space group I4mm, 107). Magnetization measurements revealed two magnetic phase transitions: from paramagnetic to ferromagnetic state at Tc = 28 K and another transition at TN = 6.6 K connected with a development of the antiferromagnetic component of magnetic moments. Both ferromagnetic and antiferromagnetic components are followed down to lowest temperature. Possible origins of the phase transition at 28 K are discussed. Paramagnetic data are well described assuming a Sm3+ ground-state-multiplet splitting in crystalline environment. Crystal field parameters are estimated and used for magnetization and specific heat calculations revealing a qualitatively good agreement with the experimental data.