Figure 1.

Phase transition and a 3-fold rotationally symmetric defect in a MoTe₂ monolayer. (a) STEM-HAADF image sequence showing two phase transitions (1H → 1T′ and 1T′ → 1H) under electron irradiation. The overlaid areas outlined by blue lines in panels a-i, a-v, and a-xi are simulated images using the black dashed regions of the models in panel b. Images without overlays are shown in Supplementary Figure 2. The unit cells of the 1H and 1T′ phases are marked by yellow dashed frames. Te vacancies are marked by white dashed circles, while the Mo atom, before and after it shifts, is marked with yellow and blue solid circles, respectively. The areas surrounded by the white dashed lines show the same region in all frames. The experimental images display raw data in false color, and the scale bar is 0.5 nm.