Decrease of dielectric loss in CaCu3Ti4O12 ceramics by La doping

We have developed a novel route to reduce the dielectric loss of CaCu3Ti4O12 (CCTO) material based on the internal‐barrier‐layer‐capacitance (IBLC) model. By the partial La‐for‐Ca substitution the dielectric loss was suppressed re‐markably while the giant dielectric constant still remains. The sample of Ca0.8La0.2Cu3Ti4O12 exhibits a high dielectric con‐ stant over 3000 and a low dissipation factor below 0.015 at 10 kHz from 180 K to 300 K. The impedance spectroscopy analysis confirms that the decrease of dielectric loss is mainly due to the increase of conductivity in the CCTO grain/subgrain. Our result is expected to be able to promote practical applications. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)