钛酸锶钡的宽频带介电谱  

Dielectric Spectrum of BST Ceramics in Wide Frequency Range

作　　者：王卫林[1] 

机构地区：[1]宜春学院理学院,江西宜春336000

出　　处：《电子元件与材料》2006年第5期49-51,68,共4页Electronic Components And Materials

基　　金：江西省教育厅科技计划资助项目(2001387)

摘　　要：利用常规固相反应法制备了系列钛酸锶钡(BaxSr1–xTiO3)(x=0.50,0.68,0.74)陶瓷。测量了样品的宽频段介电谱,发现钛酸锶钡的超低频介电谱在复介电常数平面上给出一段圆弧;但是,在高于5 Hz时偏离圆弧组成一段直线。实验表明:介质中慢极化效应的存在使得其介电弛豫普遍都不是德拜型的;在超低频至射频的广阔频段,样品的复εr不满足Kramers-Kroning(K-K)关系。实验证明在超低频下,测量εr的频域法并不适用,其物理含义还有待研究。The samples of BaxSr1-xTiO3 （x = 0.50, 0.68, 0.74） ceramics were prepared by conventional solid state reaction method, and the dielectric spectrum of BST ceramics in broad frequencies was measured. The results show that in ultra-low frequencies the dielectric spectrum is a segment of arc on complex εr plane. But when the frequencies are over 5 Hz, the experimental datum of complex εr depart from the arc significantly and fall in a straight line. The dielectric relaxation is non-Debye dielectric relaxation when slow polarization effect cannot be neglected in the samples. And from low frequency to radio frequency, the complex εr of the samples is not consistent with Kramers-Kroning relation. It indicates that frequency domain method can not be simply extended into ultra-low frequencies, while the physical meaning of experimental results is still under investigation.

关 键 词：无机非金属材料 钛酸锶钡 复εr 超低频 介电谱 非德拜驰豫 

分 类 号：O482[理学—固体物理]