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Coupled Systems Mechanics Volume 6, Number 1, March 2017 , pages 029-40 DOI: https://doi.org/10.12989/csm.2017.6.1.029 |
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Antiferroelectric and antiferrodistortive phase transitions in Ruddlesden-Popper Pb2TiO4 from first-principles |
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Tao Xu, Takahiro Shimada, Jie Wang and Takayuki Kitamura
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| Abstract | ||
| This work employed density functional theory to investigate the structural and ferroelectric properties of the Ruddlesden-Popper (RP) phase of lead titanate, Pb2TiO4, as well as its phase transitions with epitaxial strain. A wealth of novel structural instabilities, which are absent in the host PbTiO3 material, were identified in the RP phase through phonon soft-mode analysis. Our calculations showed that the ground state of Pb2TiO4 is antiferroelectric, distinct from the dominant ferroelectric phase in the corresponding host material. In addition, applied epitaxial strain was found to play a key role in the interactions among the instabilities. The induction of a sequence of antiferroelectric and antiferrodistortive (AFD) phase transitions by epitaxial strain was demonstrated, in which the ferroic instability and AFD distortion were cooperative rather than competitive, as is the case in the host PbTiO3. The RP phase in conjunction with strain engineering thus represents a new approach to creating ferroic orders and modifying the interplay among structural instabilities in the same constituent materials, enabling us to tailor the functionality of perovskite oxides for novel device applications. | ||
| Key Words | ||
| ferroelectrics; Ruddllesden-Popper phase; antiferroelectricity; strain; first-principles | ||
| Address | ||
| Tao Xu, Takahiro Shimada and Takayuki Kitamura: Department of Mechanical Engineering and Science, Kyoto University, Kyoto-Daigaku Katsura, Nishikyo-ku, Kyoto 615-8540, Japan Jie Wang: Department of Engineering Mechanics, School of Aeronautics and Astronautics, Zhejiang University, Zheda Road 38, Xihu District, Hangzhou 310027, China | ||
