title: Evidence for Dirac fermions in a honeycomb lattice based on silicon.
abstract: Silicene, a sheet of silicon atoms in a honeycomb lattice, was proposed to be a new Dirac-type electron system similar to graphene. We performed scanning tunneling microscopy and spectroscopy studies on the atomic and electronic properties of silicene on Ag(111). An unexpected √3 × √3 reconstruction was found, which is explained by an extra-buckling model. Pronounced quasiparticle interferences (QPI) patterns, originating from both the intervalley and intravalley scatter, were observed. From the QPI patterns we derived a linear energy-momentum dispersion and a large Fermi velocity, which prove the existence of Dirac fermions in silicene.
authors.affiliation: Institute of Physics, Chinese Academy of Sciences, Beijing, China.
authors.forename: Lan
authors.initials: L
authors.lastname: Chen
authors.forename: Cheng-Cheng
authors.initials: CC
authors.lastname: Liu
authors.forename: Baojie
authors.initials: B
authors.lastname: Feng
authors.forename: Xiaoyue
authors.initials: X
authors.lastname: He
authors.forename: Peng
authors.initials: P
authors.lastname: Cheng
authors.forename: Zijing
authors.initials: Z
authors.lastname: Ding
authors.forename: Sheng
authors.initials: S
authors.lastname: Meng
authors.forename: Yugui
authors.initials: Y
authors.lastname: Yao
authors.forename: Kehui
authors.initials: K
authors.lastname: Wu