First principles study on the ferroelectricity of the perovskite ABO3 ferroelectrics

• 来源期刊: 中国物理（英文版）
• 学科: 物理学
• 关键词: ferroelectrics electronic band structure phase transition
• 年，卷（期）: 2002,（7）
• 页码范围: 714-719
• 页数: 6页
• 分类号: O4
• 语种: 英文

摘要

In order to understand well the different ferroelectric behaviour of quantum paraelectrics and ferroelectrics andthe origin of the ferroelectricity of the solid solution KTa0.5Nb0.5O3(KTN), we calculated the electronic structure ofCaTiO3, BaTiO3 and KTN by first principles calculation. From total energy analysis, it is shown that, with increasingcell volume, the crystals (CaTiO3, SrTiO3) will have a ferroelectric instability. For BaTiO3, the ferroelectricity willdisappear as the cell volume is decreased. From the density of states analysis, it is shown that the hybridization betweenB d and O p is very important for the ferroelectric stability of ABO3 perovskite ferroelectrics. This is consistent withthe analysis of band structure.