Research output: Contribution to journal › Article › peer-review
Occupancy of lattice positions probed by X-ray photoelectron diffraction: A case study of tetradymite topological insulators. / Vladimirova, Nadezhda V.; Frolov, Alexander S.; Sánchez-Barriga, Jaime; Clark, Oliver J.; Matsui, Fumihiko; Усачев, Дмитрий Юрьевич; Muntwiler, Matthias; Callaert, Carolien; Hadermann, Joke; Neudachina, Vera S.; Tamm, Marina E.; Yashina, Lada V.
In: Surfaces and Interfaces, Vol. 36, 102516, 01.02.2023.Research output: Contribution to journal › Article › peer-review
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TY - JOUR
T1 - Occupancy of lattice positions probed by X-ray photoelectron diffraction: A case study of tetradymite topological insulators
AU - Vladimirova, Nadezhda V.
AU - Frolov, Alexander S.
AU - Sánchez-Barriga, Jaime
AU - Clark, Oliver J.
AU - Matsui, Fumihiko
AU - Усачев, Дмитрий Юрьевич
AU - Muntwiler, Matthias
AU - Callaert, Carolien
AU - Hadermann, Joke
AU - Neudachina, Vera S.
AU - Tamm, Marina E.
AU - Yashina, Lada V.
PY - 2023/2/1
Y1 - 2023/2/1
N2 - Occupancy of different structural positions in a crystal lattice often seems to play a key role in material properties. Several experimental techniques have been developed to uncover this issue, all of them being mostly bulk sensitive. However, many materials including topological insulators (TIs), which are among the most intriguing modern materials, are intended to be used in devices as thin films, for which the sublattice occupancy may differ from the bulk. One of the possible approaches to occupancy analysis is X-ray Photoelectron Diffraction (XPD), a structural method in surface science with chemical sensitivity. We applied this method in a case study of Sb2(Te1-xSex)3 mixed crystals, which belong to prototypical TIs. We used high-angle annular dark field (HAADF) scanning transmission electron microscopy (STEM) as a reference method to verify our analysis. We revealed that the XPD data for vacuum cleaved bulk crystals are in excellent agreement with the reference ones. Also, we demonstrate that the anion occupancy near a naturally formed surface can be rather different from that of the bulk. The present results are relevant for a wide range of compositions where the system remains a topological phase, as we ultimately show by probing the transiently occupied topological surface state above the Fermi level by ultrafast photoemission.
AB - Occupancy of different structural positions in a crystal lattice often seems to play a key role in material properties. Several experimental techniques have been developed to uncover this issue, all of them being mostly bulk sensitive. However, many materials including topological insulators (TIs), which are among the most intriguing modern materials, are intended to be used in devices as thin films, for which the sublattice occupancy may differ from the bulk. One of the possible approaches to occupancy analysis is X-ray Photoelectron Diffraction (XPD), a structural method in surface science with chemical sensitivity. We applied this method in a case study of Sb2(Te1-xSex)3 mixed crystals, which belong to prototypical TIs. We used high-angle annular dark field (HAADF) scanning transmission electron microscopy (STEM) as a reference method to verify our analysis. We revealed that the XPD data for vacuum cleaved bulk crystals are in excellent agreement with the reference ones. Also, we demonstrate that the anion occupancy near a naturally formed surface can be rather different from that of the bulk. The present results are relevant for a wide range of compositions where the system remains a topological phase, as we ultimately show by probing the transiently occupied topological surface state above the Fermi level by ultrafast photoemission.
KW - HAADF STEM
KW - Occupancy
KW - Tetradymite
KW - Topological insulators
KW - X-ray photoelectron diffraction
UR - https://www.mendeley.com/catalogue/b3efd9a8-4da0-3b1b-83cb-4cb205589af8/
U2 - 10.1016/j.surfin.2022.102516
DO - 10.1016/j.surfin.2022.102516
M3 - Article
VL - 36
JO - Surfaces and Interfaces
JF - Surfaces and Interfaces
SN - 2468-0230
M1 - 102516
ER -
ID: 106602522