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arXiv · 2003.00486

Bi2W2O9: a potentially antiferroelectric Aurivillius phase

Hania Djani·Emma. E. McCabe·W. Zhang·P. S. Halasyamani·A. Feteira·J. Bieder·E. Bousquet·Ph. Ghosez
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Abstract

Ferroelectric tungsten-based Aurivillius oxides are naturally stable superlattice structures, in which A-site deficient perovskite blocks [WnO3n+1]-2 (n = 1, 2, 3, ...) interleave with fluorite-like bismuth oxide layers [Bi2O2]+2 along the c -axis. In the n = 2 Bi2W2O9 phase, an in-plane antipolar distortion dominates but there has been controversy as to the ground state symmetry. Here we show, using a combination of first-principles density functional theory calculations and experiments, that the ground state is a non-polar phase of Pnab symmetry. We explore the energetics of metastable phases and the potential for antiferroelectricity in this n=2 Aurivillius phase.

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Hania Djani, Emma. E. McCabe, W. Zhang, P. S. Halasyamani, A. Feteira, J. Bieder, E. Bousquet, Ph. Ghosez. 2020-03-01. Bi2W2O9: a potentially antiferroelectric Aurivillius phase. https://doi.org/10.1103/physrevb.101.134113

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