Fig. 1: Dilution of Nb dopants in WS2 monolayers.
From: Nb impurity-bound excitons as quantum emitters in monolayer WS2
a Schematic illustration depicting the preparation of WS2 monolayers with ultra-dilute Nb dopants. CVD denotes chemical vapour deposition and AFM represents atomic force microscopy. b AFM height image of the encapsulated sample after tip cleaning. Shown below the image is the height profile along a line crossing the sample, with its position indicated on the image. Scale bar is 1 µm. c Magnified high-angle annular dark field-scanning transmission electron microscopy (HAADF-STEM) image of Nb dopant in the WS2, accompanied by the corresponding intensity profile integrated across the row of W atoms where the Nb is situated. d A series of HAADF-STEM images acquired on Nb-doped WS2 samples at different doping concentrations. Scale bar is 1 nm.
