摘要
The voltage tunability of Pb（Fe1/2Nb1/2）1-xTixO3 single crystals is investigated at a low electric field （〈 130 V//cm） in a low frequency range （〈 1 MHz）. The results show that the capacitance is strongly suppressed by the applied de biases for both the rhombohedral sample and the tetragonal sample. A negative voltage tunability is only detected in the tetragonal sample. The origin of the giant tunability and the negative tunability is discussed based on the multipolarization-mechanism model and the equivalent circuit model, respectively. It is ascribed to the interracial polarization at the interface of electrode/sample.
The voltage tunability of Pb（Fe1/2Nb1/2）1-xTixO3 single crystals is investigated at a low electric field （〈 130 V//cm） in a low frequency range （〈 1 MHz）. The results show that the capacitance is strongly suppressed by the applied de biases for both the rhombohedral sample and the tetragonal sample. A negative voltage tunability is only detected in the tetragonal sample. The origin of the giant tunability and the negative tunability is discussed based on the multipolarization-mechanism model and the equivalent circuit model, respectively. It is ascribed to the interracial polarization at the interface of electrode/sample.
基金
Supported by the National Natural Science Foundation of China under Grant No 10401004. Professor F. Lu and Dr. Q. J. Cai are gratefully acknowledged for the dielectric measurements. The authors also thank Professor H. Luo at Shanghai Institute of Ceramics （CAS） for providing us with part of the samples.
