利用固相反应烧结法制备了层状钙钛矿锰氧化物LaSr2Mn2-xCuxO7多晶样品. 通过X射线衍射仪、超导量子干涉仪、直流四探针法对其结构和磁性、电特性进行了研究. 结果表明, 样品均为Sr3Ti2O7型单相多晶, 属四方晶系, 空间群为I4/mmm. 10％Cu的替代, 破坏了LaSr2Mn2O7的电荷有序态, 从而呈现出一种典型的自旋玻璃特性, 在T=225K发生自旋冻结. 电性测量表明, Cu的替代, 破坏了LaSr2Mn2O7的导电特性, 使此材料在整个观察的温区呈现绝缘体特性, 进一步影响了其输运性性.
Layered perovskite LaSr2Mn2-xCuxO7 polycrystalline samples were prepared by solid state reaction. Structure and magnetic as well as electric properties were nvestigated
by X-ray diffraction, superconductor quantum interference device and direct current four probe method. The samples have the single phase with layered perovskite structure and the space group is I4/mmm. The substitution of 10％ copper destroys the charge order of LaSr2Mn2O7. Characteristic spin glass state occurs on the LaSr2MnxCuxO7, and the spin frozen temperature is near 225K. The electric properties show that the LaSr2Mn2O7 sample’s conduction characters are influenced by the substitution of 10％ Cu, which keeps in the insulator state from 77K to room temperature. At the same time, transport properties are changed by the substitution of 10％ copper. layered perovskite; LaSr2Mn 2-x CuxO7; magnetic properties; electrical properties
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