High Magnetic Anisotropy and Magnetocaloric Effects in Single-Crystal Cr₂Te₃

We report a systematic investigation of anisotropic magnetocaloric effects in single-crystal Cr2Te3. Single-crystal samples are synthesized by chemical vapor transport and characterized by X-ray and Laue diffraction methods. The maximum magnetic entropy change −ΔSMmax is 4.50 J kg–1 K–1 for the easy c-axis (3.36 J kg–1 K–1 for the hard axis along ab-plane), and the relative cooling power (RCP) is 296.7 J kg–1 for the easy c-axis (183.84 J kg–1 for the hard axis along ab-plane) for a magnetic field change of 9 T near the Curie temperature. The magneto-crystalline anisotropy constant Ku is estimated to be 580.12 kJ m–3 at 140 K, decreasing to 148.60 kJ m–3 at 168 K. Meanwhile, the maximum of the rotational magnetic entropy change −ΔSMR(T, H) between the c-axis and the ab-plane is about 1.14 J kg–1 K–1 for magnetic-field change of 9 T. The critical exponents are estimated by analyzing magnetocaloric effects, which indicate a 2D-Ising type magnetic system. The accuracy of estimated critical exponents is verified by scaling analysis. The maximum magnetic entropy change −ΔSMmax ≈ 5.25 J kg–1 K–1 (along the c-axis) and the corresponding adiabatic temperature change ΔTad ≈ 3.31 K (along the c-axis) are estimated by analyzing heat capacity measurements with a magnetic field up to 9 T.