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Title: Semimetallic transport properties of epitaxially stabilized perovskite CaIrO{sub 3} films

Abstract

We report on the synthesis and transport properties of perovskite (Pv) CaIrO{sub 3} thin films. The Pv phase of CaIrO{sub 3} was stabilized by epitaxial growth on SrTiO{sub 3}, (LaAlO{sub 3}){sub 0.3}(Sr{sub 2}AlTaO{sub 6}){sub 0.7}, and LaAlO{sub 3} substrates with strong tensile, weak tensile, and compressive strains, respectively. The resistivity of these films showed a poorly metallic behavior. The Hall resistivity exhibited a sign change as a function of temperature and a nonlinear magnetic-field dependence, which clearly indicated the coexistence of electrons and holes and hence supported that Pv CaIrO{sub 3} films are semimetallic. The observed robustness of the semimetallic ground state against tensile and compressive strains is consistent with the presence of symmetry-protected Dirac points (nodes) around the Fermi level that prohibits the system from becoming a band insulator.

Authors:
 [1];  [2];  [3];  [1];  [4]
  1. Department of Physics, University of Tokyo, Hongo 7-3-1, Bunkyo-ku, Tokyo 113-0033 (Japan)
  2. RIKEN Center for Emergent Matter Science (CEMS), Wako, Saitama 351-0198 (Japan)
  3. Institute for Solid State Physics, University of Tokyo, Kashiwanoha 5-1-5, Kashiwa, Chiba 277-8581 (Japan)
  4. (Germany)
Publication Date:
OSTI Identifier:
22483147
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 107; Journal Issue: 1; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; ALUMINATES; EPITAXY; FERMI LEVEL; GROUND STATES; LANTHANUM COMPOUNDS; MAGNETIC FIELDS; NONLINEAR PROBLEMS; PEROVSKITE; STRAINS; STRONTIUM TITANATES; SUBSTRATES; SYNTHESIS; TEMPERATURE DEPENDENCE; THIN FILMS

Citation Formats

Hirai, Daigorou, E-mail: dhirai@issp.u-tokyo.ac.jp, Matsuno, Jobu, Nishio-Hamane, Daisuke, Takagi, Hidenori, and Max-Plank-Institute for Solid State Research, Heisenbergstrasse 1, Stuttgart 70569. Semimetallic transport properties of epitaxially stabilized perovskite CaIrO{sub 3} films. United States: N. p., 2015. Web. doi:10.1063/1.4926723.
Hirai, Daigorou, E-mail: dhirai@issp.u-tokyo.ac.jp, Matsuno, Jobu, Nishio-Hamane, Daisuke, Takagi, Hidenori, & Max-Plank-Institute for Solid State Research, Heisenbergstrasse 1, Stuttgart 70569. Semimetallic transport properties of epitaxially stabilized perovskite CaIrO{sub 3} films. United States. doi:10.1063/1.4926723.
Hirai, Daigorou, E-mail: dhirai@issp.u-tokyo.ac.jp, Matsuno, Jobu, Nishio-Hamane, Daisuke, Takagi, Hidenori, and Max-Plank-Institute for Solid State Research, Heisenbergstrasse 1, Stuttgart 70569. 2015. "Semimetallic transport properties of epitaxially stabilized perovskite CaIrO{sub 3} films". United States. doi:10.1063/1.4926723.
@article{osti_22483147,
title = {Semimetallic transport properties of epitaxially stabilized perovskite CaIrO{sub 3} films},
author = {Hirai, Daigorou, E-mail: dhirai@issp.u-tokyo.ac.jp and Matsuno, Jobu and Nishio-Hamane, Daisuke and Takagi, Hidenori and Max-Plank-Institute for Solid State Research, Heisenbergstrasse 1, Stuttgart 70569},
abstractNote = {We report on the synthesis and transport properties of perovskite (Pv) CaIrO{sub 3} thin films. The Pv phase of CaIrO{sub 3} was stabilized by epitaxial growth on SrTiO{sub 3}, (LaAlO{sub 3}){sub 0.3}(Sr{sub 2}AlTaO{sub 6}){sub 0.7}, and LaAlO{sub 3} substrates with strong tensile, weak tensile, and compressive strains, respectively. The resistivity of these films showed a poorly metallic behavior. The Hall resistivity exhibited a sign change as a function of temperature and a nonlinear magnetic-field dependence, which clearly indicated the coexistence of electrons and holes and hence supported that Pv CaIrO{sub 3} films are semimetallic. The observed robustness of the semimetallic ground state against tensile and compressive strains is consistent with the presence of symmetry-protected Dirac points (nodes) around the Fermi level that prohibits the system from becoming a band insulator.},
doi = {10.1063/1.4926723},
journal = {Applied Physics Letters},
number = 1,
volume = 107,
place = {United States},
year = 2015,
month = 7
}
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