Evidences of inner Se ordering in topological insulator PbBi₂Te₄-PbBi₂Se₄-PbSb₂Se₄ solid solutions.

ABSTRACT: In topological insulators (TIs), carriers originating from non-stoichiometric defects hamper bulk insulation. In (Bi,Sb)₂(Te,Se)₃ TIs (BSTS TIs), however, Se atoms strongly prefer specific atomic sites in the crystal structure (Se ordering), and this ordering structure suppresses the formation of point defects and contributes to bulk insulation. It has accelerated the understanding of TIs' surface electron properties and device application. In this study, we select Pb(Bi,Sb)₂(Te,Se)₄ (Pb-BSTS) TIs, which are reported to have larger bandgap compared to counterpart compound BSTS TIs. The Se ordering geometry was investigated by combining state-of-the-art scanning transmission electron microscopy and powder X-ray diffractometry. We demonstrated the

SUBMITTER: Hattori Y 

PROVIDER: S-EPMC7224274 | biostudies-literature | 2020 May

REPOSITORIES: biostudies-literature