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Tunable and sizable band gap in silicene by surface adsorption.

ABSTRACT: Opening a sizable band gap without degrading its high carrier mobility is as vital for silicene as for graphene to its application as a high-performance field effect transistor (FET). Our density functional theory calculations predict that a band gap is opened in silicene by single-side adsorption of alkali atom as a result of sublattice or bond symmetry breaking. The band gap size is controllable by changing the adsorption coverage, with an impressive maximum band gap up to 0.50 eV. The ab initio quantum transport simulation of a bottom-gated FET based on a sodium-covered silicene reveals a transport gap, which is consistent with the band gap, and the resulting on/off current ratio is up to 10(8). Therefore, a way is paved for silicene as the channel of a high-performance FET.

SUBMITTER: Quhe R

PROVIDER: S-EPMC3497012 | biostudies-literature | 2012

REPOSITORIES: biostudies-literature

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Tunable and sizable band gap in silicene by surface adsorption.

Quhe Ruge R Fei Ruixiang R Liu Qihang Q Zheng Jiaxin J Li Hong H Xu Chengyong C Ni Zeyuan Z Wang Yangyang Y Yu Dapeng D Gao Zhengxiang Z Lu Jing J

Scientific reports 20121114

Opening a sizable band gap without degrading its high carrier mobility is as vital for silicene as for graphene to its application as a high-performance field effect transistor (FET). Our density functional theory calculations predict that a band gap is opened in silicene by single-side adsorption of alkali atom as a result of sublattice or bond symmetry breaking. The band gap size is controllable by changing the adsorption coverage, with an impressive maximum band gap up to 0.50 eV. The ab init ...[more]

PMID: 23152944

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