%0 Journal Article
%A Zsurka, Eduárd
%A Wang, Cheng
%A Legendre, Julian
%A Di Miceli, Daniele
%A Serra, Llorenç
%A Grützmacher, Detlev
%A Schmidt, Thomas L.
%A Rüssmann, Philipp
%A Moors, Kristof
%T Low-energy modeling of three-dimensional topological insulator nanostructures
%J Physical review materials
%V 8
%N 8
%@ 2475-9953
%C College Park, MD
%I APS
%M FZJ-2024-05736
%P 084204
%D 2024
%X We develop an accurate nanoelectronic modeling approach for realistic three-dimensional topological insulator nanostructures and investigate their low-energy surface-state spectrum. Starting from the commonly considered four-band k·p bulk model Hamiltonian for the Bi2⁢Se3 family of topological insulators, we derive new parameter sets for Bi2⁢Se3, Bi2⁢Te3, and Sb2⁢Te3. We consider a fitting strategy applied to ab initio band structures around the Γ point that ensures a quantitatively accurate description of the low-energy bulk and surface states while avoiding the appearance of unphysical low-energy states at higher momenta, something that is not guaranteed by the commonly considered perturbative approach. We analyze the effects that arise in the low-energy spectrum of topological surface states due to band anisotropy and electron-hole asymmetry, yielding Dirac surface states that naturally localize on different side facets. In the thin-film limit, when surface states hybridize through the bulk, we resort to a thin-film model and derive thickness-dependent model parameters from ab initio calculations that show good agreement with experimentally resolved band structures, unlike the bulk model that neglects relevant many-body effects in this regime. Our versatile modeling approach offers a reliable starting point for accurate simulations of realistic topological material-based nanoelectronic devices.
%F PUB:(DE-HGF)16
%9 Journal Article
%U <Go to ISI:>//WOS:001302143800001
%R 10.1103/PhysRevMaterials.8.084204
%U https://juser.fz-juelich.de/record/1031556