High Magnetic Anisotropy and Magnetocaloric Effects in Single-Crystal Cr₂Te₃

We report a systematic investigation of anisotropic magnetocaloric effects in single-crystal Cr 2 Te 3 . Single-crystal samples are synthesized by chemical vapor transport and characterized by X-ray and Laue diffraction methods. The maximum magnetic entropy change −Δ S M max 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 K u 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 −Δ S M R ( 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 −Δ S M max ≈ 5.25 J kg –1 K –1 (along the c -axis) and the corresponding adiabatic temperature change Δ T ad ≈ 3.31 K (along the c -axis) are estimated by analyzing heat capacity measurements with a magnetic field up to 9 T.