title: Superconductivity in the antiperovskite Dirac-metal oxide Sr3-xSnO.
abstract: Investigations of perovskite oxides triggered by the discovery of high-temperature and unconventional superconductors have had crucial roles in stimulating and guiding the development of modern condensed-matter physics. Antiperovskite oxides are charge-inverted counterpart materials to perovskite oxides, with unusual negative ionic states of a constituent metal. No superconductivity was reported among the antiperovskite oxides so far. Here we present the first superconducting antiperovskite oxide Sr3-xSnO with the transition temperature of around 5 K. Sr3SnO possesses Dirac points in its electronic structure, and we propose from theoretical analysis a possibility of a topological odd-parity superconductivity analogous to the superfluid3He-B in moderately hole-doped Sr3-xSnO. We envision that this discovery of a new class of oxide superconductors will lead to a rapid progress in physics and chemistry of antiperovskite oxides consisting of unusual metallic anions.
authors.affiliation: Department of Physics, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan.
authors.forename: Mohamed
authors.initials: M
authors.lastname: Oudah
authors.affiliation: Department of Physics, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan.
authors.forename: Atsutoshi
authors.initials: A
authors.lastname: Ikeda
authors.affiliation: Department of Physics, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan.|Department of Chemistry, Faculty of Mathematics and Natural Sciences, Humboldt-Universität zu Berlin, Brook-Taylor-Strasse 2, Berlin 12489, Germany.
authors.forename: Jan Niklas
authors.initials: JN
authors.lastname: Hausmann
authors.affiliation: Department of Physics, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan.
authors.forename: Shingo
authors.identifier: 0000-0002-7476-3604
authors.initials: S
authors.lastname: Yonezawa
authors.affiliation: Department of Applied Physics, Graduate School of Engineering, Nagoya University, Nagoya 464-8603, Japan.
authors.forename: Toshiyuki
authors.initials: T
authors.lastname: Fukumoto
authors.affiliation: Department of Applied Physics, Graduate School of Engineering, Nagoya University, Nagoya 464-8603, Japan.|Institute for Advanced Research, Nagoya University, Nagoya 464-8601, Japan.
authors.forename: Shingo
authors.initials: S
authors.lastname: Kobayashi
authors.affiliation: Yukawa Institute for Theoretical Physics, Kyoto University, Kyoto 606-8502, Japan.
authors.forename: Masatoshi
authors.initials: M
authors.lastname: Sato
authors.affiliation: Department of Physics, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan.
authors.forename: Yoshiteru
authors.initials: Y
authors.lastname: Maeno