Fig. 3: Identification of inter-layer stacking vectors.
From: Mottness versus unit-cell doubling as the driver of the insulating state in 1T-TaS2
a A schematic showing the in-plane displacements or phase shifts Δϕ, associated with steps of a pristine cleaved step-terrace morphology resulting from the ACAC structure. Δϕ alternates between zero and non-zero. b The same STM topography shown in Fig. 2, with the SD cluster centres in Regions 3 & 4 marked with white dots. The lower two terraces are shown to be in phase with each other, indicating that they belong to the same BL. The lattice from the lower two terraces is extended to the left-hand-side of the field-of-view. The cluster centres in Regions 1 & 2 are shown with red and grey dots, respectively. c, d The relative positions of the top terrace clusters with respect to the SD motifs of the underlying BL. e Schematic depictions of the inter-layer stacking configuration for each region, to which we attribute the DOS spectra shown in Fig. 2. The layer in Region 2 that we interpret as extrinsically re-stacked is shown in grey.
