Spin-momentum locking in topological insulators and materials with Rashba-type interactions is an extremely attractive feature for novel spintronic devices and is therefore under intense investigation. Significant efforts are underway to identify new material systems with spin-momentum locking, but also to create heterostructures with new spintronic functionalities. In the present study we address both subjects and investigate a van der Waals-type heterostructure consisting of the topological insulator Bi$_2$Se$_3$ and a single Se-Ta-Se triple-layer (TL) of H-type TaSe$_2$ grown by a method which exploits an interface reaction between the adsorbed metal and selenium. We then show, using surface x-ray diffraction, that the symmetry of the TaSe$_2$-like TL is reduced from D$_3h$ to C$_3v$ resulting from a vertical atomic shift of the tantalum atom. Spin- and momentum-resolved photoemission indicates that, owing to the symmetry lowering, the states at the Fermi surface acquire an in-plane spin component forming a surface contour with a helical Rashba-like spin texture, which is coupled to the Dirac cone of the substrate. Our approach provides a route to realize chiral two-dimensional electron systems via interface engineering in van der Waals epitaxy that do not exist in the corresponding bulk materials.
Description
Fermi surface chirality induced in a TaSe2 monosheet formed by a Ta/Bi2Se3 interface reaction | Nature Communications
%0 Journal Article
%1 noauthororeditor
%A Polyakov, Andrey
%A Mohseni, Katayoon
%A Felici, Roberto
%A Tusche, Christian
%A Chen, Ying-Jun
%A Feyer, Vitaly
%A Geck, Jochen
%A Ritschel, Tobias
%A Ernst, Arthur
%A Rubio-Zuazo, Juan
%A Castro, German R.
%A Meyerheim, Holger L.
%A Parkin, Stuart S. P.
%D 2022
%J Nat Commun
%K a
%P 2472
%R 10.1038/s41467-022-30093-1
%T Fermi surface chirality induced in a TaSe$_2$ monosheet formed by a Ta/Bi$_2$Se$_3$ interface reaction
%U https://www.nature.com/articles/s41467-022-30093-1
%V 13
%X Spin-momentum locking in topological insulators and materials with Rashba-type interactions is an extremely attractive feature for novel spintronic devices and is therefore under intense investigation. Significant efforts are underway to identify new material systems with spin-momentum locking, but also to create heterostructures with new spintronic functionalities. In the present study we address both subjects and investigate a van der Waals-type heterostructure consisting of the topological insulator Bi$_2$Se$_3$ and a single Se-Ta-Se triple-layer (TL) of H-type TaSe$_2$ grown by a method which exploits an interface reaction between the adsorbed metal and selenium. We then show, using surface x-ray diffraction, that the symmetry of the TaSe$_2$-like TL is reduced from D$_3h$ to C$_3v$ resulting from a vertical atomic shift of the tantalum atom. Spin- and momentum-resolved photoemission indicates that, owing to the symmetry lowering, the states at the Fermi surface acquire an in-plane spin component forming a surface contour with a helical Rashba-like spin texture, which is coupled to the Dirac cone of the substrate. Our approach provides a route to realize chiral two-dimensional electron systems via interface engineering in van der Waals epitaxy that do not exist in the corresponding bulk materials.
@article{noauthororeditor,
abstract = {Spin-momentum locking in topological insulators and materials with Rashba-type interactions is an extremely attractive feature for novel spintronic devices and is therefore under intense investigation. Significant efforts are underway to identify new material systems with spin-momentum locking, but also to create heterostructures with new spintronic functionalities. In the present study we address both subjects and investigate a van der Waals-type heterostructure consisting of the topological insulator Bi$_2$Se$_3$ and a single Se-Ta-Se triple-layer (TL) of H-type TaSe$_2$ grown by a method which exploits an interface reaction between the adsorbed metal and selenium. We then show, using surface x-ray diffraction, that the symmetry of the TaSe$_2$-like TL is reduced from D$_{3h}$ to C$_{3v}$ resulting from a vertical atomic shift of the tantalum atom. Spin- and momentum-resolved photoemission indicates that, owing to the symmetry lowering, the states at the Fermi surface acquire an in-plane spin component forming a surface contour with a helical Rashba-like spin texture, which is coupled to the Dirac cone of the substrate. Our approach provides a route to realize chiral two-dimensional electron systems via interface engineering in van der Waals epitaxy that do not exist in the corresponding bulk materials.},
added-at = {2022-05-10T15:41:35.000+0200},
author = {Polyakov, Andrey and Mohseni, Katayoon and Felici, Roberto and Tusche, Christian and Chen, Ying-Jun and Feyer, Vitaly and Geck, Jochen and Ritschel, Tobias and Ernst, Arthur and Rubio-Zuazo, Juan and Castro, German R. and Meyerheim, Holger L. and Parkin, Stuart S. P.},
biburl = {https://www.bibsonomy.org/bibtex/2deb90e41af8afa3fadddde2494e2502e/ctqmat},
day = 05,
description = {Fermi surface chirality induced in a TaSe2 monosheet formed by a Ta/Bi2Se3 interface reaction | Nature Communications},
doi = {10.1038/s41467-022-30093-1},
interhash = {d6bca257967d7b6f2aabe96e42e08c18},
intrahash = {deb90e41af8afa3fadddde2494e2502e},
journal = {Nat Commun},
keywords = {a},
month = {05},
pages = 2472,
timestamp = {2023-10-18T14:57:05.000+0200},
title = {Fermi surface chirality induced in a TaSe$_{\mathbf{2}}$ monosheet formed by a Ta/Bi$_{\mathbf{2}}$Se$_{\mathbf{3}}$ interface reaction},
url = {https://www.nature.com/articles/s41467-022-30093-1},
volume = 13,
year = 2022
}