摘要
用时域和频域方法研究了（Ｂａ１ｘＳｒｘ）ＴｉＯ３陶瓷的极性相变．类似于单晶的铁电相变所观察到的晶格软化，屏蔽电荷激发和畴运动讯号外，在陶瓷中还出现空间电荷运动的强讯号．空间电荷和电畴属于凝聚态物质的高级结构，它提供慢极化效应．慢效应使频域测量结果不能得到确定值．从统计观点给出高级结构的历史记忆效应对频域测量结果的影响；解释了频域介电常量的倒数在一级结构的转变中发生线性软化，而在高级结构的转变中发生抛物型软化．
Abstract By using frequency and time domain dielectric spectroscopy, the polar phase
transitions of (Ba 1- x Sr x )TiO 3 ceramics have been studied. Compared with the phase
transitions of a ferroelectric crystal, the motion of space charges in ceramic has been obtained
as well as lattice softening, excitation of screen charges and motion of ferroelectric domains.
Slow effect, which is contributed by ferroelectric domains and space charges, can affect the
accurate measurement by frequency domain method. In this paper we describe this influence
and explain some experimental results. The reciprocal of frequency domain dielectric constant
has a linear softening in the transition of primary structure, but has a parabolic type softening in
that of high structure.
出处
《物理学报》
SCIE
EI
CAS
CSCD
北大核心
1999年第4期721-728,共8页
Acta Physica Sinica
