Evolution of compatible laminate domain structures in ferroelectric single crystals
Evolution of compatible laminate domain structures in ferroelectric single crystals
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铁电单晶中兼容层压畴结构的演变
DOI：
10.1016/j.actamat.2012.10.015
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发表时间：
2013
期刊：
影响因子：
9.4
通讯作者：
Tsou N
中科院分区：
文献类型：
--
作者：
Tsou N
铁电单晶的机电性能和行为是由其电畴结构决定的。磁畴结构可以根据施加的电气和机械边界条件而演变，但通常通过采用多阶层压板形式的兼容微结构来保持低能量状态。在这项工作中，发展了一个磁区结构演化模型，使用变分方法来捕捉磁区壁面运动的耗散性质。该模型描述了域模式的演变，其约束是它们保持在低能量、兼容的配置中。研究了四方晶系中周期性相容层状畴图案的机电行为，如微结构演化和磁滞响应。给出了基于均匀场近似的材料响应估计，并与采用有限元分析精确计算自由能的数值模型进行了比较。通过考虑“枢轴状态”，模型中包括了从一种类型的层压域图案到另一种类型的层压域图案的微结构转变，这是由一个以上的层压图案共享的极限状态。在枢轴状态下不同微结构图案之间的转变被建模为一个分叉，其中一个材料元素在概念上沿着多条路径同时演化，代表该元素以不同方式演化的子区域。利用该模型研究了钛酸钡(BaTiO3)单晶在不同载荷下的电滞回线、蝴蝶应变环等电滞响应和开关机制。讨论了磁畴图案与铁电开关行为之间的关系。计算结果与文献中的实验数据基本吻合，再现了应力对电滞回线的影响等几个特征。
The electromechanical properties and behaviour of ferroelectric single crystals are dominated by their domain structures. The domain structure can evolve according to the applied electrical and mechanical boundary conditions, but typically maintains a low energy state by adopting compatible configurations of microstructure in the form of multi-rank laminates. In this work, a model of domain structure evolution is developed, using a variational method to capture the dissipative nature of domain wall motion. The model describes the evolution of domain patterns with the constraint that they remain in low energy, compatible configurations. The electromechanical behaviour, such as microstructure evolution and hysteresis response, of periodic compatible laminate domain patterns in the tetragonal crystal system is studied. Estimates of the material response based on uniform field approximations are developed, and compared with a numerical model in which finite element analysis is used for accurate computation of the free energy. Microstructural transitions from one type of laminate domain pattern to another are included in the model by considering “pivot states”, which are the limiting states shared by more than one laminate pattern. The transition between distinct microstructural patterns at a pivot state is modelled as a bifurcation in which a material element notionally evolves along multiple paths simultaneously, representing sub-regions of the element evolving in different ways. The model is applied to study the hysteresis responses, such as dielectric hysteresis loops and butterfly strain loops, and switching mechanism of barium titanate (BaTiO3) single crystals subjected to a variety of loads. The relationship between domain patterns and the behaviour of ferroelectric switching is discussed. The results show good general agreement with experimental data in the literature, reproducing several features such as the effect of stress on electrical hysteresis.
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钙钛矿型单晶的速率相关热机电自由能模型
DOI：
--
发表时间：
2007
期刊：
影响因子：
--
作者：
Sang
通讯作者：
Sang
影响因子：
5.3
作者：
J. Yen;Y. Shu;J. Shieh;J. Yeh
通讯作者：
J. Yen;Y. Shu;J. Shieh;J. Yeh
影响因子：
3.7
作者：
N. Tsou;P. Potnis;J. Huber
通讯作者：
N. Tsou;P. Potnis;J. Huber
影响因子：
3.2
作者：
Park, SE;Shrout, TR
通讯作者：
Shrout, TR
DOI：
--
发表时间：
2001
期刊：
影响因子：
--
作者：
S. Gill;M. Cornforth;A. Cocks
通讯作者：
A. Cocks