TY  - JOUR
AU  - Zsurka, Eduárd
AU  - Wang, Cheng
AU  - Legendre, Julian
AU  - Di Miceli, Daniele
AU  - Serra, Llorenç
AU  - Grützmacher, Detlev
AU  - Schmidt, Thomas L.
AU  - Rüssmann, Philipp
AU  - Moors, Kristof
TI  - Low-energy modeling of three-dimensional topological insulator nanostructures
JO  - Physical review materials
VL  - 8
IS  - 8
SN  - 2475-9953
CY  - College Park, MD
PB  - APS
M1  - FZJ-2024-05736
SP  - 084204
PY  - 2024
AB  - 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.
LB  - PUB:(DE-HGF)16
UR  - <Go to ISI:>//WOS:001302143800001
DO  - DOI:10.1103/PhysRevMaterials.8.084204
UR  - https://juser.fz-juelich.de/record/1031556
ER  -