Topological electronic structure and spin texture of quasi-one-dimensional higher-order topological insulator Bi₄Br₄.

ABSTRACT: The notion of topological insulators (TIs), characterized by an insulating bulk and conducting topological surface states, can be extended to higher-order topological insulators (HOTIs) hosting gapless modes localized at the boundaries of two or more dimensions lower than the insulating bulk. In this work, by performing high-resolution angle-resolved photoemission spectroscopy (ARPES) measurements with submicron spatial and spin resolution, we systematically investigate the electronic structure and spin texture of quasi-one-dimensional (1D) HOTI candidate Bi₄Br₄. In contrast to the bulk-state-dominant spectra on the (001) surface, we observe gapped surface states on the (100) surface, whose dispersion and spin-polarization agree well with our ab-initio calculations. M

SUBMITTER: Zhao W 

PROVIDER: S-EPMC10703900 | biostudies-literature | 2023 Dec

REPOSITORIES: biostudies-literature