Spin-charge interconversion in KTaO${}_3$ two-dimensional electron gases

Abstract

Oxide interfaces exhibit a broad range of physical effects stemming from broken inversion symmetry. In particular, they can display non-reciprocal phenomena when time reversal symmetry is also broken, e.g., by the application of a magnetic field. Examples include the direct and inverse Edelstein effects (DEE, IEE) that allow the interconversion between spin currents and charge currents. The DEE and IEE have been investigated in interfaces based on the perovskite SrTiO${}_3$ (STO), albeit in separate studies focusing on one or the other. The demonstration of these effects remains mostly elusive in other oxide interface systems despite their blossoming in the last decade. Here, we report the observation of both the DEE and IEE in a new interfacial two-dimensional electron gas (2DEG) based on the perovskite oxide KTaO${}_3$. We generate 2DEGs by the simple deposition of Al metal onto KTaO${}_3$ single crystals, characterize them by angle-resolved photoemission spectroscopy and magnetotransport, and demonstrate the DEE through unidirectional magnetoresistance and the IEE by spin-pumping experiments. We compare the spin-charge interconversion efficiency with that of STO-based interfaces, relate it to the 2DEG electronic structure, and give perspectives for the implementation of KTaO${}_3$ 2DEGs into spin-orbitronic devices.

References in corpus (25)

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• Enhanced Gilbert Damping in Thin Ferromagnetic Films
• Tunable Rashba spin-orbit interaction at oxide interfaces
• Highly efficient and tuneable spin-to-charge conversion through Rashba coupling at oxide interfaces
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Cited by in corpus (30)

• Oxide spin-orbitronics: spin-charge interconversion and topological spin textures
• Superfluid stiffness of a KTaO3-based two-dimensional electron gas
• Direct visualization of Rashba-split bands and spin/orbital-charge interconversion at KTaO${}_3$ interfaces
• Non-linear Transport in Non-centrosymmetric Systems: From Fundamentals to Applications
• Spontaneous rotational symmetry breaking in KTaO${}_3$ heterointerface superconductors
• The quantum metric of electrons with spin-momentum locking
• Tunable spin and orbital Edelstein effect at (111) LaAlO${}_3$/SrTiO${}_3$ interface
• Large nonlinear Hall effect and Berry curvature in KTaO3 based two-dimensional electron gas
• Room-temperature bulk plasticity and tunable dislocation densities in KTaO3
• Anisotropic Electronic Structure of the Two-Dimensional Electron Gas at the AlOx/KTaO3(110) interface
• Substrate-induced spin-torque-like signal in spin-torque ferromagnetic resonance measurement
• Ionic modulation at the LaAlO${}_3$/KTaO${}_3$ interface for extreme high-mobility two-dimensional electron gas
• Roadmap on Nanoscale Superconductivity for Quantum Technologies
• Emergence of large spin-charge interconversion at an oxidized Cu/W interface
• Spin-to-charge conversion at KTaO3(111) interfaces
• Anisotropic Rashba coupling to polar modes in KTaO3
• Theory of the inverse Rashba-Edelstein effect induced by thermal spin injection
• Hard x-ray angle-resolved photoemission from a buried high-mobility electron system
• Unconventional quantum oscillations and evidence of nonparabolic electronic states in quasi-two-dimensional electron system at complex oxide interfaces
• High stability 2D electron gases formed in Si3N4/Al//KTaO3 heterostructures: synthesis and in-depth interfacial characterization
• Edelstein Effect in Isotropic and Anisotropic Rashba Models
• Dirac-like fermions anomalous magneto-transport in a spin-polarized oxide two-dimensional electron system
• Boltzmann theory of the inverse Edelstein effect in a two-dimensional Rashba gas
• Spin Hall and Edelstein effects in a ballistic quantum dot with Rashba spin-orbit coupling
• Orbital and Spin Edelstein Effects in KTaO${}_3$(110) Two-Dimensional Electron Gases
• KTaO3(001) Preparation Methods in Vacuum: Effects on Surface Stoichiometry, Crystallography, and in-gap States
• Spontaneous nonreciprocal transport in a gate-tunable ferromagnetic Rashba 2-dimensional electron gas
• Achieving superconductivity in infinite-layer nickelate thin films by aluminum sputtering deposition
• Proximity-induced Rashba spin-orbit interaction in BaMnO${}_{\text{3}}|$KTaO${}_{\text{3}}$ heterostructure for antiferromagnetic spintronics
• Controlling Spin-Mixing Conductance in KTaO${}_3$ 2DEGs by Varying Argon-Ion Irradiation Time