title: Pressure-induced topological phases of KNa2Bi.
abstract: We report an ab initio study of the effect of hydrostatic pressure and uniaxial strain on electronic properties of KNa2Bi, a cubic bialkali bismuthide. It is found that this zero-gap semimetal with an inverted band structure at the Brillouin zone center can be driven into various topological phases under proper external pressure. We show that upon hydrostatic compression KNa2Bi turns into a trivial semiconductor with a conical Dirac-type dispersion of electronic bands at the point of the topological transition while the breaking of cubic symmetry by applying a uniaxial strain converts the compound into a topological insulator or into a three-dimensional Dirac semimetal with nontrivial surface Fermi arcs depending on the sign of strain. The calculated phonon dispersions show that KNa2Bi is dynamically stable both in the cubic structure (at any considered pressures) and in the tetragonal phase (under uniaxial strain).
authors.affiliation: Donostia International Physics Center (DIPC), 20018 San Sebastián/Donostia, Basque Country, Spain.|Karlsruher Institut für Technologie, Institut für Festkörperphysik, D-76021 Karlsruhe, Germany.|Institute of Strength Physics and Materials Science, pr. Academicheskii 2/1, 634021, Tomsk, Russian Federation.|Tomsk State University, 634050, Tomsk, Russian Federation.
authors.forename: I Yu
authors.initials: IY
authors.lastname: Sklyadneva
authors.affiliation: Tomsk State University, 634050, Tomsk, Russian Federation.|St. Petersburg State University, 199034, St. Petersburg, Russian Federation.
authors.forename: I P
authors.initials: IP
authors.lastname: Rusinov
authors.affiliation: Karlsruher Institut für Technologie, Institut für Festkörperphysik, D-76021 Karlsruhe, Germany.
authors.forename: R
authors.initials: R
authors.lastname: Heid
authors.affiliation: Karlsruher Institut für Technologie, Institut für Festkörperphysik, D-76021 Karlsruhe, Germany.
authors.forename: K-P
authors.initials: KP
authors.lastname: Bohnen
authors.affiliation: Donostia International Physics Center (DIPC), 20018 San Sebastián/Donostia, Basque Country, Spain.|Departamento de Física de Materiales, Facultad de Ciencias Químicas, UPV/EHU, Apdo. 1072, 20080 San Sebastián/Donostia, Basque Country, Spain.|Centro de Física de Materiales CFM - Materials Physics Center MPC, Centro Mixto CSIC-UPV/EHU, 20018 San Sebastian/Donostia, Spain.
authors.forename: P M
authors.initials: PM
authors.lastname: Echenique
authors.affiliation: Donostia International Physics Center (DIPC), 20018 San Sebastián/Donostia, Basque Country, Spain.|Departamento de Física de Materiales, Facultad de Ciencias Químicas, UPV/EHU, Apdo. 1072, 20080 San Sebastián/Donostia, Basque Country, Spain.|Centro de Física de Materiales CFM - Materials Physics Center MPC, Centro Mixto CSIC-UPV/EHU, 20018 San Sebastian/Donostia, Spain.
authors.forename: E V
authors.initials: EV
authors.lastname: Chulkov