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钙钛矿结构ＣａＣｕ３Ｍｎ４Ｏ１２的传统制备方法是热压法（几万个大气压，１０００℃）。人们发现它的居里点Ｔｃ＝３５５ Ｋ，磁电阻ＭＲ值比相同条件下的Ｌａ０．６Ｙ０．０７Ｃａ０．３３ＭｎＯａ大得多，并且从低温到高于居里点的温度范围内都存在较大的磁电阻值。另外，Ｃａ（Ｍｎ３－ｘ Ｃｕｘ） Ｍｎ４Ｏ１２（ｘ＝３）的饱和磁化场，在室温３００Ｋ时，饱和磁化场仅为０．０３Ｔ。本实验中，在常压和１０７０ Ｋ的条件下合成了Ｃａ（Ｍｎ３－ｘＣｕｘ）Ｍｎ４Ｏ１２，从而大大简化了Ｃａ （Ｍｎ３－ｘＣｕｘ）Ｍｎ４Ｏ１２的制备条件。关于该材料的导电机制，铁磁磁畴再取向饱和场与磁电阻饱和场相同，表明Ｃａ（Ｍｎ３－ｘ Ｃｕｘ）Ｍｎ４Ｏ１２的ＭＲ来源于磁畴间或颗粒间的隧道机制。
The traditional preparation method of perovskite structure CaCu3Mn4O12 is hot pressing (tens of thousands of atmospheres, 1000 ° C). It was found that its Curie point Tc = 355 K, MR value of magnetoresistance than under the same conditions La0.6Y0.07Ca0.33MnOa is much larger, and from the low temperature to higher than Curie temperature range there is a larger Magnetoresistive value. In addition, the saturation magnetization field of Ca (Mn3-xCux) Mn4O12 (x = 3) shows a saturation magnetization of only 0.03 T at 300K at room temperature. In this experiment, Ca (Mn3-xCux) Mn4O12 was synthesized under atmospheric pressure and 1070 K, which greatly simplified the preparation conditions of Ca (Mn3-xCux) Mn4O12. With regard to the conduction mechanism of the material, the reorientation saturation field of the ferromagnetic domains is the same as the saturation magnetization of the magnetoresistance, indicating that the MR of Ca (Mn3-xCux) Mn4O12 is derived from the inter-domain or inter-particle tunneling mechanism.