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arXiv · 1304.5025

Tunable band gap in few-layer graphene by surface adsorption

Ruge Quhe·Jianhua Ma·Zesheng Zeng·Kechao Tang·Jiaxin Zheng·Yangyang Wang·Zeyuan Ni·Lu Wang·Zhengxiang Gao·Junjie Shi·Jing Lu
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Abstract

There is a tunable band gap in ABC-stacked few-layer graphene (FLG) via applying a vertical electric field, but the operation of FLG-based field effect transistor (FET) requires two gates to create a band gap and tune channel's conductance individually. Using first principle calculations, we propose an alternative scheme to open a band gap in ABC-stacked FLG namely via single-side adsorption. The band gap is generally proportional to the charge transfer density. The capability to open a band gap of metal adsorption decreases in this order: K/Al > Cu/Ag/Au > Pt. Moreover, we find that even the band gap of ABA-stacked FLG can be opened if the bond symmetry is broken. Finally, a single-gated FET based on Cu-adsorbed ABC-stacked trilayer graphene is simulated. A clear transmission gap is observed, which is comparable with the band gap. This renders metal-adsorbed FLG a promising channel in a single-gated FET device.

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Ruge Quhe, Jianhua Ma, Zesheng Zeng, Kechao Tang, Jiaxin Zheng, Yangyang Wang, Zeyuan Ni, Lu Wang, Zhengxiang Gao, Junjie Shi, Jing Lu. 2013-05-22. Tunable band gap in few-layer graphene by surface adsorption. https://arxiv.org/abs/1304.5025

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