Fig. 6: Electronic band structures of 17- and 13-AGNRs.
From: Small bandgap in atomically precise 17-atom-wide armchair-edged graphene nanoribbons
a Series of dI/dV spectra obtained along one armchair edge of single 17-AGNR with length of 20a on Au(111) (setpoints: Vs = 2.6 V, It = 0.7 nA, spacing δx = 0.11). b Fourier-transformed map of a for 0 ≤ k (=q/2) ≤ π/a. c, d Analogous dI/dV spectral maps of single 13-AGNR with length of 20a on Au(111) for c unoccupied state (setpoints: Vs = 2.6 V, It = 0.7 nA, spacing δx = 0.11) and d occupied state (setpoints: Vs = −1.6 V, It = 0.2 nA, spacing δx = 0.11). e, f Fourier-transformed maps of c, d. g, h GW quasiparticle band structures (black curves) of freestanding g 17- and h 13-AGNRs, aligned at center of gap (0 eV). Blue dotted curves show parabolic fits in rage of 0 ≤ k ≤ 1 nm−1 to obtain band effective masses. In Fourier-transformed maps of b and e, f, red dotted curves indicate rigid-shifted quasiparticle bands of g and h to compare them with experimental band dispersions. All STS data were obtained at 5 K.
