title: Two-Dimensional Superconductivity Emerged at Monatomic Bi(2-) Square Net in Layered Y2O2Bi via Oxygen Incorporation.
abstract: Discovery of layered superconductors such as cuprates and iron-based compounds has unveiled new science and compounds. In these superconductors, quasi-two-dimensional layers including transition metal cations play principal role in the superconductivity via carrier doping by means of aliovalent-ion substitution. Here, we report on a two-dimensional superconductivity at 2 K in ThCr2Si2-type layered oxide Y2O2Bi possessing conducting monatomic Bi(2-) square net, possibly associated with an exotic superconductivity. The superconductivity emerges only in excessively oxygen-incorporated Y2O2Bi with expanded inter-net distance, in stark contrast to nonsuperconducting pristine Y2O2Bi reported previously. This result suggests that the element incorporation into hidden interstitial site could be an alternative approach to conventional substitution and intercalation methods for search of novel superconductors.
authors.affiliation: Department of Chemistry, Graduate School of Science, The University of Tokyo , Tokyo 113-0033, Japan.|Department of Chemistry, Graduate School of Science, Tohoku University , Sendai 980-8578, Japan.
authors.forename: Ryosuke
authors.initials: R
authors.lastname: Sei
authors.affiliation: Laboratory for Materials and Structures, Tokyo Institute of Technology , Yokohama 226-8503, Japan.
authors.forename: Suguru
authors.initials: S
authors.lastname: Kitani
authors.affiliation: Department of Chemistry, Graduate School of Science, Tohoku University , Sendai 980-8578, Japan.
authors.forename: Tomoteru
authors.initials: T
authors.lastname: Fukumura
authors.affiliation: Laboratory for Materials and Structures, Tokyo Institute of Technology , Yokohama 226-8503, Japan.
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Kawaji
authors.affiliation: Department of Chemistry, Graduate School of Science, The University of Tokyo , Tokyo 113-0033, Japan.
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Hasegawa