title: Surface electronic structure of the topological Kondo-insulator candidate correlated electron system SmB6.
abstract: The Kondo insulator SmB6 has long been known to exhibit low-temperature transport anomalies whose origin is of great interest. Here we uniquely access the surface electronic structure of the anomalous transport regime by combining state-of-the-art laser and synchrotron-based angle-resolved photoemission techniques. We observe clear in-gap states (up to ~4 meV), whose temperature dependence is contingent on the Kondo gap formation. In addition, our observed in-gap Fermi surface oddness tied with the Kramers' point topology, their coexistence with the two-dimensional transport anomaly in the Kondo hybridization regime, as well as their robustness against thermal recycling, taken together, collectively provide strong evidence for protected surface metallicity with a Fermi surface whose topology is consistent with the theoretically predicted topological Fermi surface. Our observations of systematic surface electronic structure provide the fundamental electronic parameters for the anomalous Kondo ground state of correlated electron material SmB6.
authors.affiliation: Joseph Henry Laboratory and Department of Physics, Princeton University, Princeton, New Jersey 08544, USA.
authors.forename: M
authors.initials: M
authors.lastname: Neupane
authors.affiliation: Joseph Henry Laboratory and Department of Physics, Princeton University, Princeton, New Jersey 08544, USA.
authors.forename: N
authors.initials: N
authors.lastname: Alidoust
authors.affiliation: Joseph Henry Laboratory and Department of Physics, Princeton University, Princeton, New Jersey 08544, USA.
authors.forename: S-Y
authors.initials: SY
authors.lastname: Xu
authors.affiliation: ISSP, University of Tokyo, Kashiwa, Chiba 277-8581, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Kondo
authors.affiliation: ISSP, University of Tokyo, Kashiwa, Chiba 277-8581, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Ishida
authors.affiliation: Department of Physics and Astronomy, University of California at Irvine, Irvine, California 92697, USA.
authors.forename: D J
authors.initials: DJ
authors.lastname: Kim
authors.affiliation: Joseph Henry Laboratory and Department of Physics, Princeton University, Princeton, New Jersey 08544, USA.
authors.forename: Chang
authors.initials: C
authors.lastname: Liu
authors.affiliation: Joseph Henry Laboratory and Department of Physics, Princeton University, Princeton, New Jersey 08544, USA.
authors.forename: I
authors.initials: I
authors.lastname: Belopolski
authors.affiliation: Department of Physics, Kyungpook National University, Daegu 702-701, Korea.
authors.forename: Y J
authors.initials: YJ
authors.lastname: Jo
authors.affiliation: Department of Physics, National Tsing Hua University, Hsinchu 30013, Taiwan.
authors.forename: T-R
authors.initials: TR
authors.lastname: Chang
authors.affiliation: 1] Department of Physics, National Tsing Hua University, Hsinchu 30013, Taiwan [2] Institute of Physics, Academia Sinica, Taipei 11529, Taiwan.
authors.forename: H-T
authors.initials: HT
authors.lastname: Jeng
authors.affiliation: Condensed Matter and Magnet Science Group, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA.
authors.forename: T
authors.initials: T
authors.lastname: Durakiewicz
authors.affiliation: National High Magnetic Field Laboratory, Florida State University, Tallahassee, Florida 32310, USA.
authors.forename: L
authors.initials: L
authors.lastname: Balicas
authors.affiliation: Department of Physics, Northeastern University, Boston, Massachusetts 02115, USA.
authors.forename: H
authors.initials: H
authors.lastname: Lin
authors.affiliation: Department of Physics, Northeastern University, Boston, Massachusetts 02115, USA.
authors.forename: A
authors.initials: A
authors.lastname: Bansil
authors.affiliation: ISSP, University of Tokyo, Kashiwa, Chiba 277-8581, Japan.
authors.forename: S
authors.initials: S
authors.lastname: Shin
authors.affiliation: Department of Physics and Astronomy, University of California at Irvine, Irvine, California 92697, USA.
authors.forename: Z
authors.initials: Z
authors.lastname: Fisk
authors.affiliation: 1] Joseph Henry Laboratory and Department of Physics, Princeton University, Princeton, New Jersey 08544, USA [2] Princeton Center for Complex Materials, Princeton University, Princeton, New Jersey 08544, USA.
authors.forename: M Z
authors.initials: MZ
authors.lastname: Hasan