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arXiv · 1606.01203

Topological defects at octahedral tilting plethora in bi-layered perovskites

F. -T. Huang·B. Gao·J. -W. Kim·X. Luo·Y. Wang·M. -W. Chu·C. -K. Chang·H. -S. Sheu·S. -W. Cheong
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Abstract

Oxygen octahedral distortions including tilts/rotations, deformations and off-centering in (layered) perovskites play the key role in their numerous functional properties. At the polar-centrosymmetric phase boundary in bi-layered perovskite Ca3-xSrxTi2O7 with x~1, we found the presence of abundant topological Z8 vortex-antivortex pairs, associated with four oxygen octahedral tilts at domains and another four different oxygen octahedral tilts at domain boundaries. Our discovery opens a new revenue to unveil topological defects associated with various types of oxygen octahedral distortions.

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F. -T. Huang, B. Gao, J. -W. Kim, X. Luo, Y. Wang, M. -W. Chu, C. -K. Chang, H. -S. Sheu, S. -W. Cheong. 2016-06-23. Topological defects at octahedral tilting plethora in bi-layered perovskites. https://doi.org/10.1038/npjquantmats.2016.17

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