Observation of domain morphology in twisted antimonene layers via moiré superlattice contrast with low energy electron microscopy

Using low energy electron microscopy we investigate the origin of the contrast between domains in a heterostructure composed of twisted two-dimensional antimonene layers. The contrast is observed in the bright-field microscopy mode under normal incidence of the electron beam. The heterostructure consists of a single-domain β phase grown on a top of two-domain α phase antimonene on a W(110) surface. We show that the observed contrast is due to the formation of two different moiré superlattices and it directly reflects the two-domain structure of α antimonene. We also demonstrate that the contrast depends on the relative symmetry and crystallography of two moiré patterns.