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应用科学学报 ›› 1988, Vol. 6 ›› Issue (1): 1-5.

• 论文 •    下一篇

低温下KTaO3陶瓷的介电非线性

陈志雄1, 王李1, L. E. CROSS2   

  1. 1. 华中工学院;
    2. MRL The Pennsylvania State University
  • 收稿日期:1987-02-09 出版日期:1988-03-31 发布日期:1988-03-31

NONLINEARITY OF DIELECTRIC RESPONSE IN KTaO3 CERAMIC AT LOW TEMPERATURE

CHEN ZHIXIONG1, WANG LI1, L. E. CROSS2   

  1. 1. Huazhong University of Science and Technology;
    2. MBL, The Pennsylvania State University
  • Received:1987-02-09 Online:1988-03-31 Published:1988-03-31

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摘要： 用均衡热压法制备的性能优良的KTaO3陶瓷,通过测量低温下介电常数与偏置电场的关系,研究它们的介电非线性.结果表明,在温度60K以下,介电常数与偏置电场强度有关;温度愈低,介电非线性愈强烈;这与KTaO3陶瓷在低温下表现出具有量子顺电性质特征相应.
根据Devonshire模型,用最小二乘法使实验数据与之相吻合,估算出KTaO3陶瓷的介电非线性系数值,并与单晶的数据进行比较.结果表明,KTaO3陶瓷与其单晶一样,也是有希望在超高频低温电子学中实现非线性相互作用的材料.

Abstract: KTaO3 ceramic with excellent dielectric properties has been made by hot isostatic pressing (HIP).
In order to study the nonlinear properties of KTaO3 ceramic at low temperature, we measured the electric-field dependence of dielectric constant under bias field up to 16 kV/cm and between temperatures from 4.2 K to 100K.
It was found that dielectric constant depends on the bias field at temperatures below 60K and the nonlinearity of dielectric response rises strikingly with decreasing temperature. It is related to the incipient ferro-electricity of KTaO3 ceramic at low temperature.
We evaluated the values for nonlinear dielectric response coefficients of KTaO3 ceramic while the Devonshire model was used to fit the experimental data. The values were compared with that of the nonlinear dielectric response cofficients of KTaO3 single crystal which had previously been obtained by both measuring dielectric constants and the phonon frequencies of transverse optical modes in the presense of bias fields.