title: Quasi one dimensional Dirac electrons on the surface of Ru₂Sn₃.
abstract: We present an ARPES study of the surface states of Ru2Sn3, a new type of a strong 3D topological insulator (TI). In contrast to currently known 3D TIs, which display two-dimensional Dirac cones with linear isotropic dispersions crossing through one point in the surface Brillouin Zone (SBZ), the surface states on Ru2Sn3 are highly anisotropic, displaying an almost flat dispersion along certain high-symmetry directions. This results in quasi-one dimensional (1D) Dirac electronic states throughout the SBZ that we argue are inherited from features in the bulk electronic structure of Ru2Sn3 where the bulk conduction bands are highly anisotropic. Unlike previous experimentally characterized TIs, the topological surface states of Ru2Sn3 are the result of a d-p band inversion rather than an s-p band inversion. The observed surface states are the topological equivalent to a single 2D Dirac cone at the surface Brillouin zone.
authors.affiliation: Department of Chemistry, Princeton University, Princeton, New Jersey, 08544, USA.
authors.forename: Q D
authors.initials: QD
authors.lastname: Gibson
authors.affiliation: Leibniz Institute for Solid State and Materials Research, IFW Dresden, D-01069 Dresden, Germany.
authors.forename: D
authors.initials: D
authors.lastname: Evtushinsky
authors.affiliation: Max-Planck-Institut für Festkörperforschung Heisenbergstraße 1, 70569 Stuttgart, Germany.
authors.forename: A N
authors.initials: AN
authors.lastname: Yaresko
authors.affiliation: Leibniz Institute for Solid State and Materials Research, IFW Dresden, D-01069 Dresden, Germany.
authors.forename: V B
authors.initials: VB
authors.lastname: Zabolotnyy
authors.affiliation: Department of Chemistry, Princeton University, Princeton, New Jersey, 08544, USA.
authors.forename: Mazhar N
authors.initials: MN
authors.lastname: Ali
authors.affiliation: Department of Chemistry, Princeton University, Princeton, New Jersey, 08544, USA.
authors.forename: M K
authors.initials: MK
authors.lastname: Fuccillo
authors.affiliation: Leibniz Institute for Solid State and Materials Research, IFW Dresden, D-01069 Dresden, Germany.
authors.forename: J
authors.initials: J
authors.lastname: Van den Brink
authors.affiliation: 1] Leibniz Institute for Solid State and Materials Research, IFW Dresden, D-01069 Dresden, Germany [2] Institute for Solid State Physics, Technical University Dresden, D-01171 Dresden, Germany.
authors.forename: B
authors.initials: B
authors.lastname: Büchner
authors.affiliation: Department of Chemistry, Princeton University, Princeton, New Jersey, 08544, USA.
authors.forename: R J
authors.initials: RJ
authors.lastname: Cava
authors.affiliation: Leibniz Institute for Solid State and Materials Research, IFW Dresden, D-01069 Dresden, Germany.
authors.forename: S V
authors.initials: SV
authors.lastname: Borisenko