Fig. 1: Ptychographic reconstruction of twisted SrTiO3 bilayer.
From: Polar vortex hidden in twisted bilayers of paraelectric SrTiO3
a Schematics illustrating the sample preparation process and experimental setup for electron ptychography. Besides is a structure model of twisted SrTiO3. Sr, Ti, and O atoms are represented by green, blue, and red spheres, respectively. b Total phase images of the upper (left) and lower layer (right) recovered using multislice ptychography. Scale bar, 2 nm. The structure model of SrTiO3 is overlaid on the phases. c Total phase image summed over the slices of the two layers, revealing the moiré pattern in the stacking region. Regions with AA and AB stacking sequences are marked with yellow and red circles, respectively. Scale bar, 2 nm.
