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arXiv · 1312.3957

Unit cell orientation of tetragonal-like BiFeO$_3$ thin films grown on highly miscut LaAlO$_3$ substrates

C. Beekman·W. Siemons·T. Z. Ward·J. D. Budai·J. Z. Tischler·R. Xu·W. Liu·N. Balke·J. H. Nam·H. M. Christen
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Abstract

Synchrotron and lab-scale x-ray diffraction shows that tetragonal-like T'-BiFeO3 films on miscut LaAlO3 substrates (miscut < 5 deg) exhibit (00l)-planes tilted away from those of the substrate as predicted by the "Nagai model" (except for miscut <0.2 deg). Tilts as large as 1 deg are achieved even in 100 nm thick films, strikingly larger than those observed in other perovskites. We attribute this to the large c/a ratio and the high crystalline coherency of the T'-BiFeO3/LaAlO3 interface. This coherency is possible through an observed "diagonal-on-diagonal" alignment. Interestingly, the substrate miscut does not influence the relative population of monoclinic domains.

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C. Beekman, W. Siemons, T. Z. Ward, J. D. Budai, J. Z. Tischler, R. Xu, W. Liu, N. Balke, J. H. Nam, H. M. Christen. 2013-12-13. Unit cell orientation of tetragonal-like BiFeO$_3$ thin films grown on highly miscut LaAlO$_3$ substrates. https://doi.org/10.1063/1.4809601

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