铁电相变的简谐子软模图像  

Harmonon Soft Modes in Ferroelectric Phase Transition

作　　者：丘翠环[1] 李智强[2] 何山[2] 陈敏[2] 

机构地区：[1]广东药学院物理教研室,广东广州510224 [2]中山大学物理系,广东广州510275

出　　处：《中山大学学报（自然科学版）》2002年第2期25-28,共4页Acta Scientiarum Naturalium Universitatis Sunyatseni

基　　金：广东省"十五"重大科技专项资助项目 (C1110 2 )

摘　　要：在自由边界条件下计算了立方钛酸钡有限尺寸晶体中原子的简谐振动模 ,发现许多简谐子软模。用这些软模花样说明了晶体冷却时发生具有a畴和c畴结构的铁电相变。理论表明铁电相变过程涉及屏蔽电荷的激发及其在界面的缓慢扩散 ,以最后得出各个电畴内部的均匀自发极化。铁电相变过程的这些细节 。The soft modes in finite-size cubic BaTiO3 crystal with free boundary were calculated,and they can be used to explain the phenomenon that crystal has the structure of a and c domains in ferroelectric phase transition while temperature reduction. The theory indicated that the process of ferroelectric phase transition was involved in the excitation of screen charges and slow diffusion on their interface till homogeneous spontaneous polarization in each electric domain. All above details were strongly proved by the experiments.

关 键 词：铁电相变 软模图像 简谐子软模 钛酸钡晶体 晶格动力学 简谐振动模 

分 类 号：O733.1[理学—晶体学]