Universal role of combined symmetry for the protection of the Dirac cone in antiferromagnetic topological insulators
Antiferromagnetic topological insulators (AFM TIs) are predicted to exhibit exotic physical properties such as gigantic optical and topological magnetoelectric responses. While a key to achieving such phenomena relies on how to break the symmetry protecting the Dirac-cone surface state (SS) and acquire the mass of Dirac fermions, the mechanism has yet to be clarified. To address this issue, we carried out microfocused angle-resolved photoemission spectroscopy for GdBi hosting the type-II AFM order, and uncovered the stripe-type $2\ifmmode\times\else\texttimes\fi{}1$ reconstruction of the Fermi surface associated with the AFM band folding. Intriguingly, in contrast to NdBi with the type-I AFM order displaying the surface-selective Dirac-fermion mass, GdBi shows massless behavior irrespective of AFM domains due to the robust topological protection. These results strongly suggest a crucial role of the $\mathrm{\ensuremath{\Theta}}{\mathit{T}}_{\mathrm{D}}$ (time-reversal and translational) symmetry to create the Dirac-fermion mass in AFM TIs.
Authors
- T. Takahashi (ORCID: https://orcid.org/0000-0001-7717-6512)
- S. Souma (ORCID: https://orcid.org/0000-0003-2460-4602)
- K. Ozawa (ORCID: https://orcid.org/0000-0003-2157-4671)
- Hiroshi Kumigashira (ORCID: https://orcid.org/0000-0003-4668-2695)
- T. Sato (ORCID: https://orcid.org/0000-0002-4544-5463)
- K. Nakayama (ORCID: https://orcid.org/0000-0003-2462-2253)
- Asuka Honma (ORCID: https://orcid.org/0009-0000-5972-209X)
- Koji Horiba (ORCID: https://orcid.org/0000-0002-1124-0451)
- Miho Kitamura (ORCID: https://orcid.org/0000-0002-9961-9019)
- Tamio Oguchi (ORCID: https://orcid.org/0000-0001-7109-2801)
- Noriaki Kimura (ORCID: https://orcid.org/0000-0002-0041-3847)
- Yongjian Wang (ORCID: https://orcid.org/0000-0001-5921-1986)
- Kunihiko Yamauchi (ORCID: https://orcid.org/0000-0002-9265-1091)
- Daichi Takane
- N. Kabeya (ORCID: https://orcid.org/0000-0001-7659-6208)
- Yoichi Ando (ORCID: https://orcid.org/0000-0002-3553-3355)
Institutions
- High Energy Accelerator Research Organization (JP)
- University of Cologne (DE)
- Tohoku University (JP)
- National Institutes for Quantum Science and Technology (JP)
- The University of Osaka (JP)
Publication Details
- Journal
- Physical review. B./Physical review. B
- Published
- 2024-09-26
- DOI
- https://doi.org/10.1103/physrevb.110.115152
- Citations
- 2
- Primary Topic
- Topological Materials and Phenomena
- Type
- article
- Field-Weighted Citation Impact
- 0.68
Funders
- Deutsche Forschungsgemeinschaft
- Japan Science and Technology Corporation
- Japan Society for the Promotion of Science
- Division for Interdisciplinary Advanced Research and Education, Tohoku University
- Core Research for Evolutional Science and Technology