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arXiv · 1011.5089

Design of a low band gap oxide ferroelectric: Bi$_6$Ti$_4$O$_{17}$

Bo Xu·David J. Singh·Valentino R. Cooper·Yuan Ping Feng
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Abstract

A strategy for obtaining low band gap oxide ferroelectrics based on charge imbalance is described and illustrated by first principles studies of the hypothetical compound Bi$_6$Ti$_4$O$_{17}$, which is an alternate stacking of the ferroelectric Bi$_4$Ti$_3$O$_{12}$. We find that this compound is ferroelectric, similar to Bi$_4$Ti$_3$O$_{12}$ although with a reduced polarization. Importantly, calculations of the electronic structure with the recently developed functional of Tran and Blaha yield a much reduced band gap of 1.83 eV for this material compared to Bi$_4$Ti$_3$O$_{12}$. Therefore, Bi$_6$Ti$_4$O$_{17}$ is predicted to be a low band gap ferroelectric material.

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Bo Xu, David J. Singh, Valentino R. Cooper, Yuan Ping Feng. 2011-03-15. Design of a low band gap oxide ferroelectric: Bi$_6$Ti$_4$O$_{17}$. https://doi.org/10.1209/0295-5075%2F94%2F37006

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