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[(a)–(c)] LEEM images of three samples, with red dots to denote the typical terrace widths used in this paper. The three shades in these images, white, gray, and black, are buffer layer, monolayer graphene, and bilayer graphene, respectively. Inset of (a): reflectivity as a function of incident kinetic energy for the buffer layer and first monolayer through fourth monolayer (bottom to top). The number of dips in the reflectivity curves is equal to the number of graphene layers. The dotted line denotes 4.2 eV electron kinetic energy, which is used in (a)–(c).
[(a)–(e)] ARPES spectra of samples with increasing monolayer graphene terrace width, S1 through S5. Inset of (a) shows the Brillouin zone of graphene. The horizontal line through the point shows the measurement geometry in -space. The large and small pink left-right arrows give the peak separation and width of the Fermi level MDC of S1.
(a) The Fermi level MDCs with incremental offset. (b) The electronic charge carrier density as a function of terrace width. (c) Fermi level MDC widths, extracted from panel (a).
(a) Low and (b) high binding-energy dispersions as a function of terraces widths. Note that the small curvature at in panel (a) is due to the finite energy resolution of the experiment. (c) Fermi velocities vs terrace widths. Inset of (a) and (b) shows a cartoon of the graphene band structure as a function of terraces width. The boxed regions in the insets denote the regions of the dispersions of (a) and (b).
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