角度分解光電子分光で調べる擬一次元ビスマスハライドのトポロジカル電子状態

抄録

Quasi-one-dimensional materials offer an ideal playground to investigate weak topological insulators (WTIs) and higher-order topological insulators (HOTIs), since their characteristic boundary states emerge in the naturally cleaved surfaces. Utilizing laser-based angle-resolved photoemission spectroscopy (ARPES) and synchrotron-based nano-ARPES, we show evidence of a WTI phase in β-Bi₄I₄ and a HOTI phase in Bi₄Br₄.