Extended Data Fig. 5: Graphene spiral structure.

(a) Atomic force microscopy imaging of GS structures. (b) The zoom-in of topography over the region indicated by the white square in (a) showing four intertwined spirals structure. (c,d) Schematic representation of initial state and final structure of graphene spiral in (a). Note: as-grown GS is fabricated by in situ observation assisted CVD method (see Methods in main text).