Direct visualization of Rashba-split bands and spin/orbital-charge interconversion at KTaO${}_3$ interfaces

Abstract

Rashba interfaces have emerged as promising platforms for spin-charge interconversion through the direct and inverse Edelstein effects. Notably, oxide-based two-dimensional electron gases (2DEGs) display a large and gate-tunable conversion efficiency, as determined by transport measurements. However, a direct visualization of the Rashba-split bands in oxide 2DEGs is lacking, which hampers an advanced understanding of their rich spin-orbit physics. Here, we investigate KTaO${}_3$-2DEGs and evidence their Rashba-split bands using angle resolved photoemission spectroscopy. Fitting the bands with a tight-binding Hamiltonian, we extract the effective Rashba coefficient and bring insight into the complex multiorbital nature of the band structure. Our calculations reveal unconventional spin and orbital textures, showing compensation effects from quasi-degenerate band pairs which strongly depend on in-plane anisotropy. We compute the band-resolved spin and orbital Edelstein effects, and predict interconversion efficiencies exceeding those of other oxide 2DEGs. Finally, we suggest design rules for Rashba systems to optimize spin-charge interconversion performance.

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• Spin and orbital Edelstein effect in a bilayer system with Rashba interaction
• Giant Rashba splitting in PtTe/PtTe${}_2$ heterostructure
• Anisotropic Electronic Structure of the Two-Dimensional Electron Gas at the AlOx/KTaO3(110) interface
• Revealing Hidden Spin Polarization in Centrosymmetric van der Waals Materials on Ultrafast Timescales
• Spin-phonon interactions and magnetoelectric coupling in Co${}_4$$B_2$O${}_9$ ($B$ = Nb, Ta)
• Spin-to-charge conversion at KTaO3(111) interfaces
• Anisotropic Rashba coupling to polar modes in KTaO3
• Theory of spin and orbital charge conversion at the surface states of Bi_{1-x}Sb_x topological insulator
• Theory of the inverse Rashba-Edelstein effect induced by thermal spin injection
• Unconventional quantum oscillations and evidence of nonparabolic electronic states in quasi-two-dimensional electron system at complex oxide interfaces
• Edelstein Effect in Isotropic and Anisotropic Rashba Models
• Duality and degeneracy lifting in two-dimensional electron liquids on SrTiO${}_3$(001)
• Evidence of linear and cubic Rashba effect in non-magnetic heterostructure
• Filtering Spin and Orbital Moment in Centrosymmetric Systems
• Spin and Orbital Rashba response in ferroelectric polarized PtSe${}_2$/MoSe${}_2$/LiNbO${}_3$ heterostructures
• Hallmarks of spin textures for high-harmonic generation in two-dimensional materials
• Rashba splitting in polar-nonpolar sandwich heterostructure : A DFT Study
• Boltzmann theory of the inverse Edelstein effect in a two-dimensional Rashba gas
• KTaO3(001) Preparation Methods in Vacuum: Effects on Surface Stoichiometry, Crystallography, and in-gap States
• Proximity-induced Rashba spin-orbit interaction in BaMnO${}_{\text{3}}|$KTaO${}_{\text{3}}$ heterostructure for antiferromagnetic spintronics
• Orientation-dependent superconductivity and electronic structure of the rare-earth metal/KTaO3 interfaces
• Achieving superconductivity in infinite-layer nickelate thin films by aluminum sputtering deposition