2:30 PM - 2:45 PM
△ [9p-W521-4] Quantum Hall effect and band dispersion of turbostratic stacked graphene
Keywords:graphene, quantum Hall effect, band dispersion
Graphene continues to attract intense interest, especially as a two-dimensional electron system in which charge carriers are governed by Dirac equation in the limit of zero mass. Interestingly, recent studies of Raman spectroscopy imply that the Dirac-cone dispersion is maintained even when CVD monolayer graphene is multiply stacked. In addition, the dramatic improvement of carrier mobility is reported in such turbostratic stacked graphene. Here we verify the improvement of carrier mobility and investigate the band dispersion through Landau level (LL) splitting deduced by the quantum Hall effect. The presence of the finite interlayer coupling is suggested from the breakdown of electron-hole symmetry and the degeneracy of LL splitting. Although the Dirac-cone band feature is not explicitly observed in our samples, the carrier mobility of the turbostratic stacked graphene was much higher than that of CVD monolayer graphene.