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arXiv · 0710.5208

Effect of epitaxial strain on ferroelectric polarization in multiferroic BiFeO3 films

Dae Ho Kim·Ho Nyung Lee·Michael D. Biegalski·Hans M. Christen
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Abstract

Multiferroic BiFeO3 epitaxial films with thickness ranging from 40 nm to 960 nm were grown by pulsed laser deposition on SrTiO3 (001) substrates with SrRuO3 bottom electrodes. X-ray characterization shows that the structure evolves from angularly-distorted tetragonal with c/a ~ 1.04 to more bulk-like distorted rhombohedral (c/a ~ 1.01) as the strain relaxes with increasing thickness. Despite this significant structural evolution, the ferroelectric polarization along the body diagonal of the distorted pseudo-cubic unit cells, as calculated from measurements along the normal direction, barely changes.

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Dae Ho Kim, Ho Nyung Lee, Michael D. Biegalski, Hans M. Christen. 2007-12-11. Effect of epitaxial strain on ferroelectric polarization in multiferroic BiFeO3 films. https://doi.org/10.1063/1.2830799

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