Interfacial-Strain-Induced Structural and Polarization Evolutions in Epitaxial Multiferroic BiFeO3 (001) Thin Films
Interfacial-Strain-Induced Structural and Polarization Evolutions in Epitaxial Multiferroic BiFeO3 (001) Thin Films
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外延多铁 BiFeO3 (001) 薄膜中界面应变引起的结构和极化演化
DOI：
10.1021/am508511y
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发表时间：
2015-02-04
影响因子：
9.5
通讯作者：
Yang, Guozhen
中科院分区：
文献类型：
--
作者：
Guo, Haizhong;Zhao, Ruiqiang;Yang, Guozhen
Varying the film thickness is a precise route to tune the interfacial strain to manipulate the properties of the multiferroic materials. Here, to explore the effects of the interfacial strain on the properties of the multiferroic BiFeO3 films, we investigated thickness-dependent structural and polarization evolutions of the BiFeO3 films. The epitaxial growth with an atomic stacking sequence of BiO/TiO2 at the interface was confirmed by scanning transmission electron microscopy. Combining X-ray diffraction experiments and first-principles calculations, a thickness-dependent structural evolution was observed from a fully strained tetragonality to a partially relaxed one without any structural phase transition or rotated twins. The tetragonality (c/a) of the BiFeO3 films increases as the film thickness decreases, while the polarization is in contrast with this trend, and the size effect including the depolarization field plays a crucial role in this contradiction in thinner films. These findings offer an alternative strategy to manipulate structural and polarization properties by tuning the interfacial strain in epitaxial multiferroic thin films.
