Fig. 4: Flat-band integer Landau level gap.
From: Direct probing of energy gaps and bandwidth in gate-tunable flat band graphene systems
a Longitudinal resistance Rxx and Hall resistance Rxy as a function of ntot and B. The Dirac LLs degeneracy is lifted, and \({{{\mathrm{L}}}}{{{{\mathrm{L}}}}}_{N=-1}^{D}\) splits into four mini-bands \({{{\mathrm{L}}}}{{{{\mathrm{L}}}}}_{l}^{D}\) indicated by the purple and red dashed lines. The black dashed lines indicate the flat band LLs. As DMG LLs offer Chern number offset, the corresponding Chern number C (indicated by black number) equals Cf (indicated by yellow number) + CD, Cf and CD are Chern numbers of the TMBG flat band and DMG Dirac band respectively. b The flat band integer Landau level gap (\({{{\mathrm{L}}}}{{{{\mathrm{L}}}}}_{l=-2}^{f}\)). Multiple As, Bs represent gap edges of \({{{\mathrm{L}}}}{{{{\mathrm{L}}}}}_{l=-2}^{f}\) and the estimated gap △N = ∣μA − μB∣ = 4.1 ± 0.9 meV is averaged through different \({{{\mathrm{L}}}}{{{{\mathrm{L}}}}}_{l}^{D}\).
