电循环作用下CaCu_3Ti_4O_(12)的电阻突变行为研究

Study on the resistance transition behavior of CaCu_3Ti_4O_(12) by electrical conditioning

用电循环处理方法研究空气烧结CaCu3Ti4O12陶瓷样品的I-V特性曲线与样品缺陷之间的关系.结果表明,通过电循环处理,CaCu3Ti4O12的电阻随循环次数增加而减小,在特定温度和电压下出现电阻突然减小,I-V特性曲线从非线性转变为欧姆线性的奇特行为,这是CaCu3Ti4O12研究中观察到的新现象.I-V曲线说明发生电阻突变时样品温度与电压的关系满足线性关系,通过高低电阻随温度的变化拟合得到CaCu3Ti4O12的晶粒、晶界激活能分别为0.06 eV、0.56 eV.

We prepared Ca Cu3Ti4O12 ceramic samples sintered in air. The relationship between I-V curvesand defects of Ca Cu3Ti4O12 were studied by the electrical conditioning method. The result shows that theresistance of Ca Cu3Ti4O12 decreases with electrical conditioning processes and a dramatic transition ofresistance take places at a certain temperature and voltage,in which the I-V curve suddenly changes fromnonlinearity to ohmic linearity. This is a new phenomenon observed for Ca Cu3Ti4O12. Besides,the resistance ofgrain and grain boundary in CCTO are separated by the relaxation of I- V characteristics. The criticaltemperature of I-V transition and the activation energy are also obtained respectively for the grain（0.06 e V） andgrain boundary（0.56 e V） by fitting the experimental data.