Significantly enhanced breakdown field of 24.52 kV cm⁻¹ as well as noteworthy nonlinear coefficient of 8.11 and low dielectric loss of 0.077 were obtained in Ca_0.6Sr_0.4Cu₃Ti₄O₁₂ ceramic. It was proved from impedance spectra that improved breakdown field was attributed to enhanced grain boundary resistance and elevated Schottky barrier height, which was further found resulting from reduced donor densities in C-V measurements. In addition, it was found that the activation energy originated from oxygen vacancies was increased, indicating the generation of oxygen vacancies was suppressed. Since oxygen vacancies acted as donors in depletion layers, it is reasonable to deduce that the reduced donor density was mainly ascribed to the decreased oxygen vacancies. In conclusion, maximum integrated action of strong solid solution effect and weak Sr-stretching effect was achieved when Sr/Ca ratio is 40/60, leading to greatly elevated potential barrier height and enhanced breakdown field consequently.

在Ca _0.6 Sr _0.4 Cu ₃ Ti ₄ O ₁₂陶瓷中，击穿场显着增强，达到24.52 kV cm ^-1，值得注意的非线性系数为8.11，低介电损耗为0.077 。从阻抗谱证明，改善的击穿场归因于增强的晶界电阻和升高的肖特基势垒高度，这进一步被发现是由于降低了CV的施主密度测量。另外，发现源自氧空位的活化能增加，表明氧空位的产生被抑制。由于氧空位在耗尽层中充当施主，因此可以合理地推断出，降低的施主密度主要归因于氧空位的降低。综上所述，当Sr / Ca比为40/60时，可实现强固溶效应和弱Sr拉伸效应的最大积分作用，从而导致势垒高度大大提高，击穿场增强。