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用脉冲激光沉积 (PLD)方法成功地制备了双层钙钛矿结构的La2 - 2xSr1 + 2xMn2 O7(x =0 32 )单相薄膜 .这种薄膜生长在具有不同晶格参数的两种衬底上 .测量发现 ,两种衬底上生长的La2 - 2xSr1 + 2xMn2 O7(x =0 32 )薄膜具有迥然不同的金属 绝缘体转变温度TM -I及其他物性 .界面应力的研究表明这是衬底晶格常数不同引起膜内应变的结果 .在衬底的压应力下 ,薄膜的电阻 温度曲线的峰值 (TM -I)向高温移动且电阻率 (ρ)下降 ;相反 ,对于衬底张应力下的薄膜 ,TM -I下降 ρ上升 .这些结果可以用双交换模型做很好的解释 .
A single phase thin film of La2 - 2xSr1 + 2xMn2 O7 (x = 0 32) with double perovskite structure was successfully prepared by pulsed laser deposition (PLD) method.The films were grown on two substrates with different lattice parameters The results show that La2 - 2xSr1 + 2xMn2 O7 (x = 0 32) thin films grown on the two substrates have very different transition temperature TM -I and other physical properties.The interfacial stress studies show that this is the substrate crystal As a result, the peak value of the resistance temperature curve (TM -I) of the film moves to high temperature and the resistivity (ρ) decreases under the compressive stress of the substrate. On the contrary, Film, TM-I drop ρ rise These results can be well explained by the double exchange model.