Dual topological states in the layered titanium-based oxypnictide superconductor BaTi2Sb2O

Z. Huang; W. L. Liu; H. Y. Wang; Y. L. Su; Z. T. Liu; X. B. Shi; S. Y. Gao; Z. Y. Chen; Y. J. Yan; Z. C. Jiang; Z. H. Liu; J. S. Liu; X. L. Lu; Y. C. Yang; R. X. Zhou; W. Xia; Y. B. Huang; S. Qiao; W. W. Zhao; Y. F. Guo; G. Li; D. W. Shen

doi:10.1038/s41535-022-00477-z

npj Quantum Materials (Jun 2022)

Dual topological states in the layered titanium-based oxypnictide superconductor BaTi2Sb2O

Z. Huang,
W. L. Liu,
H. Y. Wang,
Y. L. Su,
Z. T. Liu,
X. B. Shi,
S. Y. Gao,
Z. Y. Chen,
Y. J. Yan,
Z. C. Jiang,
Z. H. Liu,
J. S. Liu,
X. L. Lu,
Y. C. Yang,
R. X. Zhou,
W. Xia,
Y. B. Huang,
S. Qiao,
W. W. Zhao,
Y. F. Guo,
G. Li,
D. W. Shen

Affiliations

Z. Huang: Center for Excellence in Superconducting Electronics, State Key Laboratory of Functional Materials for Informatics, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences
W. L. Liu: Center for Excellence in Superconducting Electronics, State Key Laboratory of Functional Materials for Informatics, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences
H. Y. Wang: School of Physical Science and Technology, ShanghaiTech University
Y. L. Su: School of Physical Science and Technology, ShanghaiTech University
Z. T. Liu: Center for Excellence in Superconducting Electronics, State Key Laboratory of Functional Materials for Informatics, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences
X. B. Shi: State Key Laboratory of Advanced Welding and Joining, Harbin Institute of Technology
S. Y. Gao: Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences
Z. Y. Chen: Hefei National Laboratory for Physical Sciences at the Microscale, and Department of Physics, University of Science and Technology of China
Y. J. Yan: Hefei National Laboratory for Physical Sciences at the Microscale, and Department of Physics, University of Science and Technology of China
Z. C. Jiang: Center for Excellence in Superconducting Electronics, State Key Laboratory of Functional Materials for Informatics, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences
Z. H. Liu: Center for Excellence in Superconducting Electronics, State Key Laboratory of Functional Materials for Informatics, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences
J. S. Liu: Center for Excellence in Superconducting Electronics, State Key Laboratory of Functional Materials for Informatics, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences
X. L. Lu: Center for Excellence in Superconducting Electronics, State Key Laboratory of Functional Materials for Informatics, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences
Y. C. Yang: Center for Excellence in Superconducting Electronics, State Key Laboratory of Functional Materials for Informatics, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences
R. X. Zhou: School of Physical Science and Technology, ShanghaiTech University
W. Xia: School of Physical Science and Technology, ShanghaiTech University
Y. B. Huang: Shanghai Synchrotron Radiation Facility, Shanghai Advanced Research Institute, Chinese Academy of Sciences
S. Qiao: Center for Excellence in Superconducting Electronics, State Key Laboratory of Functional Materials for Informatics, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences
W. W. Zhao: State Key Laboratory of Advanced Welding and Joining, Harbin Institute of Technology
Y. F. Guo: School of Physical Science and Technology, ShanghaiTech University
G. Li: School of Physical Science and Technology, ShanghaiTech University
D. W. Shen: Center for Excellence in Superconducting Electronics, State Key Laboratory of Functional Materials for Informatics, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences

DOI: https://doi.org/10.1038/s41535-022-00477-z
Journal volume & issue: Vol. 7, no. 1
pp. 1 – 7

Abstract

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Abstract Topological superconductors have long been predicted to host Majorana zero modes which obey non-Abelian statistics and have potential for realizing non-decoherence topological quantum computation. However, material realization of topological superconductors is still a challenge in condensed matter physics. Utilizing high-resolution angle-resolved photoemission spectroscopy and first-principles calculations, we predict and then unveil the coexistence of topological Dirac semimetal and topological insulator states in the vicinity of Fermi energy (E F ) in the titanium-based oxypnictide superconductor BaTi2Sb2O. Further spin-resolved measurements confirm its spin-helical surface states around E F , which are topologically protected and give an opportunity for realization of Majorana zero modes and Majorana flat bands in one material. Hosting dual topological states, the intrinsic superconductor BaTi2Sb2O is expected to be a promising platform for further investigation of topological superconductivity.

Published in npj Quantum Materials

ISSN: 2397-4648 (Online)
Publisher: Nature Portfolio
Country of publisher: United Kingdom
LCC subjects: Technology: Electrical engineering. Electronics. Nuclear engineering: Materials of engineering and construction. Mechanics of materials; Science: Physics: Atomic physics. Constitution and properties of matter
Website: https://www.nature.com/npjquantmats/

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