Figure 2: Visualizing the distortion domains.
From: Chemically induced Jahn–Teller ordering on manganite surfaces
(a) Unoccupied-state STM image of LCMO surface with a bias voltage of +1.6 V, 21 × 21 nm. Blue and red circles mark the adatom positions that have zigzag distortions in [110] and [1–10] directions for eye guiding, respectively. An expanded view of the local adatoms with the ABCDO coordinates superimposed is shown in the inset. (b) The distortion angle map of (a) showing two domains with different orientations of distortion angle. See the text for the definition of the sign and value of the angles. The map is plotted such that the colour represents the distortion angle for the adatoms at the locations of the colour spots. Circles are added to better illustrate the locations. (c) Histogram of distortion angles for (a), showing two distinct peaks corresponding to two distortion domains with different orientations. The inset shows the definition of the distortion angles. (d) Occupied-state STM image with a bias voltage of −1.75 V, 20 × 20 nm. (e) The distortion angle map of (d) that does not show any distinct domains comparing with (b). (f) Histogram of distortion angles for (d), showing smaller distortions. The FFT of (a) and (d) are shown in the insets of (c) and (f). Spots in the white circles are from (√2 × √2)R45°; extra spots pointed by red arrows are only shown in the unoccupied-state image, but not in the occupied-state image.
