Strain and Size Effects on Ferroelectric Properties of BaTiO3 Nanofilms
SANG Yong-Liang1, LIU Bin1,2, FANG Dai-Ning1
1FML, Department of Engineering Mechanics, Tsinghua University, Beijing 1000842State Key Laboratory of Structural Analysis for Industrial Equipment, Dalian University of Technology, Dalian 116023
Strain and Size Effects on Ferroelectric Properties of BaTiO3 Nanofilms
SANG Yong-Liang1;LIU Bin1,2;FANG Dai-Ning1
1FML, Department of Engineering Mechanics, Tsinghua University, Beijing 1000842State Key Laboratory of Structural Analysis for Industrial Equipment, Dalian University of Technology, Dalian 116023
摘要The strain and size effects on the ferroelectric properties of BaTiO3 films are studied using the molecular dynamics method based on a shell model. It is found that from microscopic view, these two effects share the same physical nature, i.e., the resulting crystal cell distortions lead to the separation of negative and positive charge centres. The strain and size effects are therefore coupled, and the critical thicknesses of films would depend on the in-plane strains, which provides a possible interpretation on the discrepancies among the experimental measurements of the critical thicknesses. A polarization map is given to clearly reflect the relations among the size, strain and polarization of the nano films.
Abstract：The strain and size effects on the ferroelectric properties of BaTiO3 films are studied using the molecular dynamics method based on a shell model. It is found that from microscopic view, these two effects share the same physical nature, i.e., the resulting crystal cell distortions lead to the separation of negative and positive charge centres. The strain and size effects are therefore coupled, and the critical thicknesses of films would depend on the in-plane strains, which provides a possible interpretation on the discrepancies among the experimental measurements of the critical thicknesses. A polarization map is given to clearly reflect the relations among the size, strain and polarization of the nano films.
SANG Yong-Liang;LIU Bin;FANG Dai-Ning. Strain and Size Effects on Ferroelectric Properties of BaTiO3 Nanofilms[J]. 中国物理快报, 2008, 25(3): 1113-1116.
SANG Yong-Liang, LIU Bin, FANG Dai-Ning. Strain and Size Effects on Ferroelectric Properties of BaTiO3 Nanofilms. Chin. Phys. Lett., 2008, 25(3): 1113-1116.
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2008, Vol. 25 
