第一原理計算に基づくダンベル型グラフェンナノリボンの電気伝導特性

抄録

Graphene is two dimensional structure with honey comb like hexagonal lattice with carbon atoms. Graphene nanoribbons (GNRs), graphene with nanoscale width, are expected to show a semiconductive property. Therefore next generation devices such as high-speed transistors and strain sensors using GNRs have been studied. However, schottky barrier should be decreased between electrodes and semiconductors. Dumbbell-shape GNRs (DGNRs) is proposed to solve this problem. This structure consists of an electrode part with wider GNR and a device part with narrower GNR. It is reported that electron orbital distribution is localized in DGNRs. In this study, we studied on electronic states and transmission property of DGNR17-7, which consists of AGNR17 and AGNR7, based on first principle calculation of density functional theory using SIESTA and TranSIESTA module. It is shown that the orbital distribution of HOMO of DGNR17-7 is correspond to that of electrode part. At the same time, band gap of DGNR17-7 gets smaller than AGNR7 by the effect of electrode part. In the analysis of I-V property, DGNR17-7 and AGNR7 shows same tendency. These result imply that the transmission property of DGNR17-7 is similar to device part and DGNR17-7 can be applied to devices as semiconductors.