Nanoscale twisted bilayer graphene (TBG) is quite instable and will changeits structure to Bernal (or AB-stacking) bilayer with a much lower energy.Therefore, the lack of nanoscale TBG makes its electronic properties notaccessible in experiment up to now. In this work, a special confined TBG isobtained in the overlaid area of two continuous misoriented graphene sheets.The width of the confined region of the TBG changes gradually from about 22 nmto 0 nm. By using scanning tunnelling microscopy, we studied carefully thestructure and the electronic properties of the nanoscale TBG. Our resultsindicate that the low-energy electronic properties, including twist-induced vanHove singularities (VHSs) and spatial modulation of local density-of-state, arestrongly affected by the translational symmetry breaking of the nanoscale TBG.Whereas, the electronic properties above the energy of the VHSs are almost notinfluenced by the quantum confinement even when the width of the TBG is reducedto only a single moire spot.
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