title: Substrate-induced structures of bismuth adsorption on graphene: a first principles study.
abstract: The geometric and electronic properties of Bi-adsorbed monolayer graphene, enriched by the strong effect of a substrate, are investigated by first-principles calculations. The six-layered substrate, corrugated buffer layer, and slightly deformed monolayer graphene are all simulated. Adatom arrangements are thoroughly studied by analyzing the ground-state energies, bismuth adsorption energies, and Bi-Bi interaction energies of different adatom heights, inter-adatom distance, adsorption sites, and hexagonal positions. A hexagonal array of Bi atoms is dominated by the interactions between the buffer layer and the monolayer graphene. An increase in temperature can overcome a ∼50 meV energy barrier and induce triangular and rectangular nanoclusters. The most stable and metastable structures agree with the scanning tunneling microscopy measurements. The density of states exhibits a finite value at the Fermi level, a dip at ∼-0.2 eV, and a peak at ∼-0.6 eV, as observed in the experimental measurements of the tunneling conductance.
authors.affiliation: Department of Physics, National Cheng Kung University, 701 Tainan, Taiwan. jcahuang@mail.ncku.edu.tw mflin@mail.ncku.edu.tw.
authors.forename: Shih-Yang
authors.initials: SY
authors.lastname: Lin
authors.forename: Shen-Lin
authors.initials: SL
authors.lastname: Chang
authors.forename: Hsin-Hsien
authors.initials: HH
authors.lastname: Chen
authors.forename: Shu-Hsuan
authors.initials: SH
authors.lastname: Su
authors.forename: Jung-Chun
authors.initials: JC
authors.lastname: Huang
authors.forename: Ming-Fa
authors.initials: MF
authors.lastname: Lin