Theoretical work on magnetocaloric effect in La0.75Ca0.25MnO3
Theoretical work on magnetocaloric effect in La0.75Ca0.25MnO3
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DOI：
10.1007/s40145-012-0027-8
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发表时间：
2012-10
影响因子：
16.9
通讯作者：
M. A. Hamad
中科院分区：
文献类型：
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作者：
M. A. Hamad
在这项工作中，应用一个现象学模型来描述la0.75 ca0.25 mno3体系从铁磁状态到顺磁状态的二阶相变附近的磁热效应。基于该模型，可以通过计算磁化强度随温度的变化来预测不同外加磁场下材料的磁热特性。当外加磁场变化4 T时，在257 K处磁熵变化达到峰值，约为5.39 J/（kg·K）。ΔSMdistribution比钆均匀得多，这是埃里克森循环磁制冷机所需要的。
In this work, a phenomenological model is applied to describe the magnetocaloric effect for the La0.75Ca0.25MnO3system near a second-order phase transition from a ferromagnetic to a paramagnetic state. Based on this model, it can predict the values of the magnetocaloric properties from calculation of magnetization as a function of temperature under different external magnetic fields. The magnetic entropy change reaches a peak of about 5.39 J/(kg·K) at 257 K upon 4 T applied field variation. The ΔSMdistribution is much more uniform than that of gadolinium, which is desirable for an Ericson-cycle magnetic refrigerator.