Electric field dependence of characteristic temperatures in PbSc0.5Ta0.5O3 and Pb0.78Ba0.22Sc0.5Ta0.5O3 relaxors studied via acoustic emission
Electric field dependence of characteristic temperatures in PbSc0.5Ta0.5O3 and Pb0.78Ba0.22Sc0.5Ta0.5O3 relaxors studied via acoustic emission
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通过声发射研究 PbSc0.5Ta0.5O3 和 Pb0.78Ba0.22Sc0.5Ta0.5O3 弛豫剂特征温度的电场依赖性
DOI：
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发表时间：
2011
期刊：
影响因子：
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通讯作者：
M. Roth
中科院分区：
文献类型：
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作者：
E. Dul’kin;B. Mihailova;M. Gospodinov;M. Roth
用声发射研究了两种模型弛豫铁电体PbSc0.5Ta0.5O3（自发对铁电相转变）和Pb0.78Ba0.22Sc0.5Ta0.5O3（无外电场时无长程铁电序）在200-600 K的直流电场e下发生对铁电向反铁电转变，这两种化合物在略高于介电介电常数最大值的Tn处表现出对铁电向反铁电转变。两种化合物的中间温度T*均随e的增加而线性增加，dT*/dE斜率大于铁电转变温度Tc，与BaTiO3中的转变现象相似。T*(E)的增加被认为是由于极性纳米区域内偶极极化的增强。
Two model relaxor ferroelectrics PbSc0.5Ta0.5O3 (undergoing a spontaneous para-to-ferroelectric phase transformation) and Pb0.78Ba0.22Sc0.5Ta0.5O3 (no long-range ferroelectric order in the absence of an external electric field) were studied by acoustic emission in the temperature range 200–600 K under a dc field E. Both compounds exhibit a para-to-antiferroelectric transformation at Tn, which is slightly above the temperature of the dielectric-permittivity maximum. For both compounds the intermediate temperature T* increases linearly with increasing E. The dT*/dE slope is larger than that of the ferroelectric transformation temperature Tc, similar to the transformation phenomena in BaTiO3. The T*(E) increase is suggested to be due to enhanced dipole polarizations inside the polar nanoregions.