@article{LiYanThomaleetal.2015, author = {Li, Gang and Yan, Binghai and Thomale, Ronny and Hanke, Werner}, title = {Topological nature and the multiple Dirac cones hidden in Bismuth high-Tc superconductors}, series = {Scientific Reports}, volume = {5}, journal = {Scientific Reports}, number = {10435}, doi = {10.1038/srep10435}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-148569}, year = {2015}, abstract = {Recent theoretical studies employing density-functional theory have predicted BaBiO\(_{3}\) (when doped with electrons) and YBiO\(_{3}\) to become a topological insulator (TI) with a large topological gap (~0.7 eV). This, together with the natural stability against surface oxidation, makes the Bismuth-Oxide family of special interest for possible applications in quantum information and spintronics. The central question, we study here, is whether the hole-doped Bismuth Oxides, i.e. Ba\(_{1-X}\)K\(_{X}\)BiO\(_{3}\) and BaPb\(_{1-X}\)Bi\(_{X}\)O\(_{3}\), which are "high-Tc" bulk superconducting near 30 K, additionally display in the further vicinity of their Fermi energy E\(_{F}\) a topological gap with a Dirac-type of topological surface state. Our electronic structure calculations predict the K-doped family to emerge as a TI, with a topological gap above E\(_{F}\). Thus, these compounds can become superconductors with hole-doping and potential TIs with additional electron doping. Furthermore, we predict the Bismuth-Oxide family to contain an additional Dirac cone below E\(_{F}\) for further hole doping, which manifests these systems to be candidates for both electron-and hole-doped topological insulators.}, language = {en} }