09:30 〜 11:30
▲ [15a-PA01-26] Electronic-structure tuning of multilayer graphene by a perpendicular electric field and stacking arrangement
キーワード：Graphene thin films, Electronic structure, Electric field
In recent year, graphene has gained significant interest in the wide areas of nanoscale sciences and technologies due to its excellent physical properties. The electronic structure of graphene is sensitive to the interlayer stacking arrangement and the number of layers [1]. Moreover, an external electric field modulates band dispersion spectra near the Fermi level of bilayer graphene [2]. However, the electronic properties of multilayer graphene under the electric field are uncertain in terms of their stacking arrangement and the number of layers. Therefore, in this work, we aim to elucidate the electronic structure of multilayer graphene under the perpendicular electric field using the density functional theory combined with the effective screening medium method.
Fig. 1 shows the electronic structure of multilayer graphene with AB and ABC stacking under the perpendicular electric field. We found that the electronic structure under the electric field strongly depends on the number of layers and their stacking arrangement. Multilayer graphene with AB stacking arrangement under the electric field is a metal or a semimetal when the multilayer graphene consists of odd or even number of layers, respectively. In contrast, the multilayer graphene with ABC stacking under the electric field is a semiconductor which possesses flat band at the valence-band and conduction-band edges, irrespective of the number of layers.
Fig. 1 shows the electronic structure of multilayer graphene with AB and ABC stacking under the perpendicular electric field. We found that the electronic structure under the electric field strongly depends on the number of layers and their stacking arrangement. Multilayer graphene with AB stacking arrangement under the electric field is a metal or a semimetal when the multilayer graphene consists of odd or even number of layers, respectively. In contrast, the multilayer graphene with ABC stacking under the electric field is a semiconductor which possesses flat band at the valence-band and conduction-band edges, irrespective of the number of layers.