Addendum to: Nature Communications https://doi.org/10.1038/s41467-023-37823-z, published online 24 April 2023

In this article, we reported a solution epitaxy of ferroelectric oxide films, focusing on single-crystal film of PbTiO3 on single-crystal Nb:SrTiO3 substrate. We would like to provide additional information to further support its epitaxy and single-crystal character by electron back-scattered diffraction (EBSD) and rocking curve analysis. Figure 1a presents a typical EBSD band contrast map of PbTiO3 film in a relatively large area, and the uniform color of the inverse pole figure (IPF) map in the Z direction (IPF Z in Fig. 1b) demonstrates that PbTiO3 film is a single crystal. Furthermore, the fullwidth at half maxima (FWHM) of the rocking curve (Fig. 1c) scanned around the (001) diffraction peak is only 0.028°, indicating a high-quality epitaxy of PbTiO3 film on the substrates.

Fig. 1 EBSD and rocking curve analysis of PbTiO3 film on (100) Nb(0.7wt%): SrTiO3 substrate. a EBSD band contrast image. b corresponding EBSD IPF Z direction color map. c rocking curve of PTO film (001) peak.