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Magnetocaloric response in anisotropic single-crystals with cubic crystal symmetry is studied. As compared to isotropic magnets where only paramagnetic-to-ferromagnetic phase transition occurs at Curie temperature ( T C = 185 K) and magnetization increases monotonously with increasing field and/or decreasing temperature, the spin reorientation phase transitions may occur at lower temperatures (∼ 115 K) as the magnetic field gets oriented along one of the cubic anisotropy easy axes and induces nonmonotonic increases in magnetization with increasing field and temperature, leading to a spike-like entropy change (−ΔSM) and positive ΔSM at TC, or move the −ΔSM peak towards higher temperatures. Finally, the power laws of maximum −ΔSM and relative cooling power with the field and the double-shifted loop results evidence that only second-order phase transition occurs and the abnormal magnetization behavior completely comes from the spin order evolution due to energy competition. Therefore, the Maxwell relation is applicable. The results are also suitable for multiple anisotropy or polycrystalline materials with well-defined domains. [ABSTRACT FROM AUTHOR]

The influence of magnetocrystalline anisotropy (K) on the magnetic entropy change (ΔSM) in single crystals under low fields (H) is studied based on unbiased Monte Carlo simulations. When H is applied perpendicular to the easy axis, the positive and negative ΔSM may coexist. The positive ΔSM peak value and its maximum value optimized by the field and the threshold of switching to negative ΔSM depend on K. Moreover, K linearly enhances the blocking temperature where the negative ΔSM maximum is obtained, associated with the decrease in the peak value with increasing K. Finally, the rotating ΔSM under a constant H may be much larger than ΔSM produced by moving the model in and out of the same H, and the best response to K is found at 86° between K and H, independent of the anisotropy magnitude. [ABSTRACT FROM AUTHOR]