Figure 2

STEM-HAADF images of LTO/STO(110). (a), (b) As-deposited film. Regions of perovskite LaTiO₃, La₅Ti₅O₁₇ (including an overlay of the atomic positions in one unit cell), and an unidentified phase are indicated. (c), (d) LTO/STO(110) after annealing at 1100 °C/4 h in air. A region of perovskite LaTiO₃ is indicated in (c). The PLS atomic positions in one unit cell is overlaid on the PLS lattice image in (d), and the position of the additional oxygen plane is indicated with an arrow. The curly bracket near the top of the image in (d) indicates a defected region in which 6 perovskite layers separate additional oxygen planes.