Origin and evolution of surface spin current in topological insulators

Abstract

The Dirac surface states of topological insulators offer a unique possibility for creating spin polarized charge currents due to the spin-momentum locking. Here we demonstrate that the control over the bulk and surface contribution is crucial to maximize the charge-to-spin conversion efficiency. We observe an enhancement of the spin signal due to surface-dominated spin polarization while freezing out the bulk conductivity in semiconducting Bi1.5Sb0.5Te1.7Se1.3 below 100K. Detailed measurements up to room temperature exhibit a strong reduction of the magnetoresistance signal between 2 and 100K, which we attribute to the thermal excitation of bulk carriers and to the electron-phonon coupling in the surface states. The presence and dominance of this effect up to room temperature is promising for spintronic science and technology.

References in corpus (26)

• Two-Dimensional Gas of Massless Dirac Fermions in Graphene
• Topological Insulators
• Discovery (theoretical prediction and experimental observation) of a large-gap topological-insulator class with spin-polarized single-Dirac-cone on the surface
• First observation of Spin-Momentum Helical Locking in Bi2Se3 and Bi2Te3, demonstration of Topological-Order at 300K and a realization of topological-transport-regime
• Topological Insulator Materials
• Spin Transfer Torque Generated by the Topological Insulator Bi_2Se_3
• Spintronics and Pseudospintronics in Graphene and Topological Insulators
• Coexistence of the topological state and a two-dimensional electron gas on the surface of Bi2Se3
• Spin Polarization and Transport of Surface States in the Topological Insulators Bi2Se3 and Bi2Te3 from First Principles
• Observation of topological surface state quantum Hall effect in an intrinsic three-dimensional topological insulator
• Fermi level dependent charge-to-spin current conversion by Dirac surface state of topological insulators
• Optimizing the Bi_(2-x)Sb_(x)Te_(3-y)Se_(y) solid solutions to approach the intrinsic topological insulator regime
• Emergent quantum confinement at topological insulator surfaces
• Electrical detection of the spin polarization due to charge flow in the surface state of the topological insulator Bi_1.5 Sb_0.5 Te_1.7 Se_1.3
• Room Temperature Electrical Detection of Spin Polarized Currents in Topological Insulators
• Surface dominated transport in single crystalline nanoflake devices of topological insulator Bi1.5Sb0.5Te1.8Se1.2
• Electrical injection and detection of spin-polarized currents in topological insulator Bi2Te2Se
• Spin-Polarized Tunneling Study on Spin-Momentum Locking in the Topological Insulators
• Efficient Spin Injection into Silicon and the Role of the Schottky Barrier
• Electron-phonon scattering in topological insulator thin films
• Switching of Charge-Current-Induced Spin Polarization in the Topological Insulator BiSbTeSe2
• Direct comparison of current-induced spin polarization in topological insulator Bi2Se3 and InAs Rashba states
• Towards the understanding of the origin of charge-current-induced spin voltage signals in the topological insulator Bi${}_2$Se${}_3$
• Surface-to-bulk scattering in topological insulator films
• Van der Waals epitaxial growth of topological insulator Bi${}_{2-x}$Sb${}_x$Te${}_{3-y}$Se${}_y$ ultrathin nanoplate on electrically insulating fluorophlogopite mica
• Self-consistent model of spin accumulation magnetoresistance in ferromagnet-insulator-semiconductor tunnel junctions

Cited by in corpus (16)

• Gate-tunable Spin-Galvanic Effect in Graphene Topological insulator van der Waals Heterostructures at Room Temperature
• Large unidirectional spin Hall and Rashba-Edelstein magnetoresistance in topological insulator/magnetic insulator heterostructures
• Tunable Electronic Properties and Large Rashba Splittings Found in Few-Layer Bi${}_2$Se${}_3$/PtSe${}_2$ Van der Waals Heterostructures
• All-electrical spin-to-charge conversion in sputtered Bi${}_x$Se${}_{1-x}$
• Opposite current-induced spin polarizations in bulk-metallic Bi2Se3 and bulk-insulating Bi2Te2Se topological insulator thin flakes
• Edelstein and inverse Edelstein effects caused by the pristine surface states of topological insulators
• Charge-spin conversion signal in WTe2 van der Waals hybrid devices with a geometrical design
• Spin torque and persistent currents caused by percolation of topological surface states
• Rashba Effect and Raman Spectra of Tl${}_2$O/PtS${}_2$ Heterostructure
• Room temperature nonlocal detection of charge-spin interconversion in a topological insulator
• Persistent currents and spin torque caused by percolated quantum spin Hall state
• Large-Scale Epitaxial Integration of Single-Crystalline BiSb Topological Insulator on GaAs (111)A
• Gate-Tunable Spin-to-Charge Conversion in Topological Insulator-Magnetic Insulator Heterostructures at Room Temperature
• Superconductivity at Pd/Bi${}_2$Se${}_3$ Interfaces Due to Self-Formed PdBiSe Interlayers
• Promoted current-induced spin polarization in inversion symmetry broken topological insulator thin films
• SnAs: a 4K weak type-II superconductor with non-trivial band topology