title: Substrate-induced symmetry breaking in silicene.
abstract: We demonstrate that silicene, a 2D honeycomb lattice consisting of Si atoms, loses its Dirac fermion characteristics due to substrate-induced symmetry breaking when synthesized on the Ag(111) surface. No Landau level sequences appear in the tunneling spectra under a magnetic field, and density functional theory calculations show that the band structure is drastically modified by the hybridization between the Si and Ag atoms. This is the first direct example demonstrating the lack of Dirac fermions in a single layer honeycomb lattice due to significant symmetry breaking.
authors.affiliation: Department of Advanced Materials Science, Graduate School of Frontier Science, The University of Tokyo, Kashiwa 5-1-5, Chiba 277-8561, Japan.
authors.forename: Chun-Liang
authors.initials: CL
authors.lastname: Lin
authors.affiliation: International Center for Materials Nanoarchitectonics (WPI-MANA), National Institute for Materials Science, 1-1 Namiki, Ibaraki 304-0044, Japan.
authors.forename: Ryuichi
authors.initials: R
authors.lastname: Arafune
authors.affiliation: Department of Advanced Materials Science, Graduate School of Frontier Science, The University of Tokyo, Kashiwa 5-1-5, Chiba 277-8561, Japan.
authors.forename: Kazuaki
authors.initials: K
authors.lastname: Kawahara
authors.affiliation: Department of Applied Chemistry, The University of Tokyo, Hongo 7-3-1, Tokyo 113-8656, Japan.
authors.forename: Mao
authors.initials: M
authors.lastname: Kanno
authors.affiliation: Department of Advanced Materials Science, Graduate School of Frontier Science, The University of Tokyo, Kashiwa 5-1-5, Chiba 277-8561, Japan.
authors.forename: Noriyuki
authors.initials: N
authors.lastname: Tsukahara
authors.affiliation: RIKEN, 2-1 Hirosawa, Saitama 351-0198, Japan.
authors.forename: Emi
authors.initials: E
authors.lastname: Minamitani
authors.affiliation: RIKEN, 2-1 Hirosawa, Saitama 351-0198, Japan.
authors.forename: Yousoo
authors.initials: Y
authors.lastname: Kim
authors.affiliation: Department of Advanced Materials Science, Graduate School of Frontier Science, The University of Tokyo, Kashiwa 5-1-5, Chiba 277-8561, Japan and Department of Applied Chemistry, The University of Tokyo, Hongo 7-3-1, Tokyo 113-8656, Japan.
authors.forename: Maki
authors.initials: M
authors.lastname: Kawai
authors.affiliation: Department of Advanced Materials Science, Graduate School of Frontier Science, The University of Tokyo, Kashiwa 5-1-5, Chiba 277-8561, Japan and Department of Applied Chemistry, The University of Tokyo, Hongo 7-3-1, Tokyo 113-8656, Japan.
authors.forename: Noriaki
authors.initials: N
authors.lastname: Takagi