2015/10/21 by Bertold Rasche, Anna Isaeva, Michael Ruck +3 · 10 citations
Materials Science · Physics and Astronomy · #2D Materials and Applications #Band gap #Character (mathematics) #Chemical bond #Electronic band structure #Graphene research and applications #Insulator (electricity) #Position (finance) #Topological Materials and Phenomena #Topological insulator #Topology (electrical circuits) #cond-mat.mtrl-sci
paper · pdf · doi:10.1038/srep20645
published in Scientific Reports 6(1), 20645 (Nature Portfolio)
arxiv created 2015/10/21 · openalex publication_date 2016/02/15 · arxiv updated 2016/06/10 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
Recently the presence of topologically protected edge-states in Bi14Rh3I9 was confirmed by scanning tunnelling microscopy consolidating this compound as a weak 3D topological insulator (TI). Here, we present a density-functional-theory-based study on a family of TIs derived from the Bi14Rh3I9 parent structure via substitution of Ru, Pd, Os, Ir and Pt for Rh. Comparative analysis of the band-structures throughout the entire series is done by means of a unified minimalistic tight-binding model that evinces strong similarity between the quantum-spin-Hall (QSH) layer in Bi14Rh3I9 and graphene in terms of Pz-molecular orbitals. Topologically non-trivial energy gaps are found for the Ir-, Rh-, Pt- and Pd-based systems, whereas the Os- and Ru-systems remain trivial. Furthermore, the energy position of the metal d-band centre is identified as the parameter which governs the evolution of the topological character of the band structure through the whole family of TIs. The d-band position is shown to correlate with the chemical bonding within the QSH layers, thus revealing how the chemical nature of the constituents affects the topological band character.