【摘 要】
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The electrical properties of cubic perovskite series,CaCu3-xTi4-xFe2xO12 with x=0.0,0.1,0.3,0.5,and 0.7,have been studied by employing current density as a function of electric field characteristics registered at different temperatures and thermal variati
【机 构】
：
Department of Physics,Saurashtra University,Rajkot 360005,India;Department of Physics,C.U.Shah Unive
论文部分内容阅读
The electrical properties of cubic perovskite series,CaCu3-xTi4-xFe2xO12 with x=0.0,0.1,0.3,0.5,and 0.7,have been studied by employing current density as a function of electric field characteristics registered at different temperatures and thermal variations of direct current electrical resistivity measurements.All of the compositions exhibit strong non-ohmic behavi-or.The concentration dependence of breakdown field,the temperature at which switching action takes place,and maximum value of current density(Jmax)has been explained on account of structural,microstructural,and positron lifetime parameters.The highest ever reported value of Jmax=327 mA/cm2 has been observed for pristine composition.The values of the nonlinear coefficient advise the suitability of ceramics for low-voltage varistor applications.The Arrhenius plots show typical semiconduct-ing nature.The activation energy values indicate that electric conduction proceeds through electrons with deformation in the system.
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