A platform for research: civil engineering, architecture and urbanism
Spin‐Momentum Locking and Ultrafast Spin‐Charge Conversion in Ultrathin Epitaxial Bi1 − xSbx Topological Insulator
The helicity of three‐dimensional (3D) topological insulator surface states has drawn significant attention in spintronics owing to spin‐momentum locking where the carriers' spin is oriented perpendicular to their momentum. This property can provide an efficient method to convert charge currents into spin currents, and vice‐versa, through the Rashba–Edelstein effect. However, experimental signatures of these surface states to the spin‐charge conversion are extremely difficult to disentangle from bulk state contributions. Here, spin‐ and angle‐resolved photo‐emission spectroscopy, and time‐resolved THz emission spectroscopy are combined to categorically demonstrate that spin‐charge conversion arises mainly from the surface state in Bi1 − xSbx ultrathin films, down to few nanometers where confinement effects emerge. This large conversion efficiency is correlated, typically at the level of the bulk spin Hall effect from heavy metals, to the complex Fermi surface obtained from theoretical calculations of the inverse Rashba–Edelstein response. Both surface state robustness and sizeable conversion efficiency in epitaxial Bi1 − xSbx thin films bring new perspectives for ultra‐low power magnetic random‐access memories and broadband THz generation.
Spin‐Momentum Locking and Ultrafast Spin‐Charge Conversion in Ultrathin Epitaxial Bi1 − xSbx Topological Insulator
The helicity of three‐dimensional (3D) topological insulator surface states has drawn significant attention in spintronics owing to spin‐momentum locking where the carriers' spin is oriented perpendicular to their momentum. This property can provide an efficient method to convert charge currents into spin currents, and vice‐versa, through the Rashba–Edelstein effect. However, experimental signatures of these surface states to the spin‐charge conversion are extremely difficult to disentangle from bulk state contributions. Here, spin‐ and angle‐resolved photo‐emission spectroscopy, and time‐resolved THz emission spectroscopy are combined to categorically demonstrate that spin‐charge conversion arises mainly from the surface state in Bi1 − xSbx ultrathin films, down to few nanometers where confinement effects emerge. This large conversion efficiency is correlated, typically at the level of the bulk spin Hall effect from heavy metals, to the complex Fermi surface obtained from theoretical calculations of the inverse Rashba–Edelstein response. Both surface state robustness and sizeable conversion efficiency in epitaxial Bi1 − xSbx thin films bring new perspectives for ultra‐low power magnetic random‐access memories and broadband THz generation.
Spin‐Momentum Locking and Ultrafast Spin‐Charge Conversion in Ultrathin Epitaxial Bi1 − xSbx Topological Insulator
Rongione, E. (author) / Baringthon, L. (author) / She, D. (author) / Patriarche, G. (author) / Lebrun, R. (author) / Lemaître, A. (author) / Morassi, M. (author) / Reyren, N. (author) / Mičica, M. (author) / Mangeney, J. (author)
Advanced Science ; 10
2023-07-01
9 pages
Article (Journal)
Electronic Resource
English
Topological Surface‐Dominated Spintronic THz Emission in Topologically Nontrivial Bi1−xSbx Films
Wiley | 2022
|Space charge limited conduction in bulk Se100−xSbx chalcogenide glasses
British Library Online Contents | 2006
|Ultrathin whitetopping gains momentum
British Library Online Contents | 1997