Fig. 2: Scanning transmission electron microscopy/energy-dispersive X-ray spectroscopy (STEM/EDX) characterization of (Pr0.85Y0.15)0.7Ca0.3CoO3-δ films.
From: Room-temperature valence transition in a strain-tuned perovskite oxide
Room-temperature STEM/EDX characterization of films on YAO (εxx = −2.10 %) and LAO (εxx = 0.25 %) substrates (where εxx is the “in-plane strain”). Atomic-resolution high-angle annular-dark-field (HAADF) STEM images on (a) YAO(101) and (b) LAO(001) substrates. The scale bars are 2 nm and the horizontal lines mark the interfaces. (c, d) EDX maps of Pr Lα (green), Co Kα (magenta), Ca Kα (orange) and Y Lα (yellow) intensities in the boxed regions in (a,b) (on YAO and LAO, respectively). (Note that due to the low Y content of these films, the Y values are subject to significant uncertainty). (e,f) Line scans of the HAADF intensity (top) and normalized elemental atomic percentages (bottom) along the atomic columns highlighted in (a-d) (on YAO and LAO, respectively). The grey vertical bands highlight columns with larger HAADF intensity and compositional fluctuations, as discussed in the text.
