Presentation Information
[17p-M_178-11]Large Rashba spin-orbit coupling induced by mirror symmetry breaking in NiTe/NiTe2
〇(P)Souren Adhikary1, Tomoaki Kameda1, Katsunori Wakabayashi1 (1.Kwansei Gakuin Univ.)
Keywords:
Heterostructure,Rashba splitting,Optically spin current generation
Spin-orbit coupling (SOC) has attracted considerable attention in materials science owing to its potential applications in next-generation information technologies, as well as its pivotal role in revealing the fundamental physics of spin [1-2]. Mirror symmetry breaking combined with strong SOC in a material can induce the Rashba effect [3]. Using density functional theory, we demonstrate that a vertical heterostructure composed of monolayer NiTe and NiTe2 exhibits pronounced Rashba spin splitting, characterized by a large Rashba parameter of 1.318 eV·Å. Although each monolayer individually preserves both mirror and inversion symmetries, stacking them into a vertical heterostructure breaks the out-of-plane mirror symmetry due to the different number of Ni layers in the two constituents (highlighted by shaded rectangles in Fig.(a)). This symmetry breaking produces a substantial interfacial electric field, which drives the large Rashba effect. Notably, the Rashba-split bands appear close to the Fermi energy (≈ 0.1 eV below), making them particularly relevant for device applications.
Furthermore, sliding the two monolayers to realize different stacking configurations effectively tunes the strength of the Rashba SOC. In addition, we show that linearly polarized light can induce a finite in-plane spin current, providing a purely optical pathway for spin-current generation and manipulation [4]. These results establish the NiTe/NiTe2 heterostructure as a promising platform for engineering Rashba-based spin physics.
Furthermore, sliding the two monolayers to realize different stacking configurations effectively tunes the strength of the Rashba SOC. In addition, we show that linearly polarized light can induce a finite in-plane spin current, providing a purely optical pathway for spin-current generation and manipulation [4]. These results establish the NiTe/NiTe2 heterostructure as a promising platform for engineering Rashba-based spin physics.