Electrical and optical properties of mixed aurivillius phase Bi7Ti4NbO21 single crystal
Electrical and optical properties of mixed aurivillius phase Bi7Ti4NbO21 single crystal
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DOI：
10.1016/s0022-3697(96)00040-6
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发表时间：
1996-12
影响因子：
4
通讯作者：
R. Maalal;R. Mühll;G. Trolliard;J. Mercurio
中科院分区：
文献类型：
--
作者：
R. Maalal;R. Mühll;G. Trolliard;J. Mercurio
用助熔剂法在Bi_2 O_3过量的条件下制备了铁电混合相Bi_7 Ti_4 Nb_（21）单晶。在室温至900 °C之间研究了介电常数、X射线衍射图、双折射和光学观察以及差示扫描量热法的热依赖性。观察到两个温度驱动的相变，第一个接近630-675 °C，在铁电态（铁I-铁II）内，第二个在830 °C，在铁电态II和顺电态之间。
Single crystals of the ferroelectric mixed Aurivillius phase Bi7Ti4NbO21have been prepared by the flux method in Bi2O3excess. Thermal dependence of dielectric permittivity, X-ray diffraction patterns, birefringence and optical observations as well as differential scanning calorimetry have been studied between room temperature and 900 °C. Two temperature driven phase transitions were observed, the first one close to 630–675 °C within a ferroelectric state (ferro I-ferro II), the second one at ≈ 830 °C, between the ferroelectric state II and the paraelectric state.