Abstract
We have performed angle-resolved photoemission spectroscopy on which is predicted to be an axion insulator in the antiferromagnetic state. By utilizing soft-x-ray and vacuum-ultraviolet photons, we revealed a three-dimensional hole pocket centered at the point of the bulk Brillouin zone together with a heavily hole-doped surface state in the paramagnetic phase. Upon entering the antiferromagnetic phase, the band structure exhibits a marked reconstruction characterized by the emergence of an “M”-shaped bulk band near the Fermi level. The qualitative agreement with first-principles band-structure calculations suggests the occurrence of bulk-band inversion at the point in the antiferromagnetic phase. We suggest that provides a good opportunity to study the exotic quantum phases associated with a possible axion-insulator phase.
- Received 22 February 2020
- Accepted 2 July 2020
DOI:https://doi.org/10.1103/PhysRevResearch.2.033342
Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI.
Published by the American Physical Society