Abstract The correlation between conductance, capacitance and oxygen content is discussed in the colossal dielectric permittivity perovskite oxide CaCu3Ti4O12. We found an unusual positive conductivity-permittivity relation which is very sensitive to the oxygen content. In particular, we ascribe the oxygen content sensitivity of both the capacitance and the conductance to a repositioning of charges on oxygen vacancy related defects and/or on the migration of the defects themselves. We find that in the charge repositioning process a Jonscher type of global conduction is accompanied by a Debye-type local electronic relaxation in and between the boundaries of a specific grain. A closer investigation of these processes suggest that the local polaronic relaxation of charges on oxygen vacancy related defects is mainly responsible for the large dielectric constant of CaCu3Ti4O12 and also for the ac conduction at low to medium temperatures.

中文翻译：

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缺氧 CaCu 3 Ti 4 O 12 中的电导率-介电常数关系

摘要 讨论了大介电常数钙钛矿氧化物CaCu3Ti4O12中电导、电容和氧含量之间的相关性。我们发现了一种不寻常的正电导率-介电常数关系，它对氧含量非常敏感。特别是，我们将电容和电导的氧含量敏感性归因于与氧空位相关的缺陷和/或缺陷本身的迁移上的电荷重新定位。我们发现在电荷重新定位过程中，Jonscher 类型的全局传导伴随着特定晶粒边界内和边界之间的德拜型局部电子弛豫。