Photoelectron spin-flipping and texture manipulation in a topological insulator

Abstract

Recently discovered materials called three-dimensional topological insulators constitute examples of symmetry protected topological states in the absence of applied magnetic fields and cryogenic temperatures. A hallmark characteristic of these non-magnetic bulk insulators is the protected metallic electronic states confined to the material's surfaces. Electrons in these surface states are spin polarized with their spins governed by their direction of travel (linear momentum), resulting in a helical spin texture in momentum space. Spin- and angle-resolved photoemission spectroscopy (spin-ARPES) has been the only tool capable of directly observing this central feature with simultaneous energy, momentum, and spin sensitivity. By using an innovative photoelectron spectrometer with a high-flux laser-based light source, we discovered another surprising property of these surface electrons which behave like Dirac fermions. We found that the spin polarization of the resulting photoelectrons can be fully manipulated in all three dimensions through selection of the light polarization. These surprising effects are due to the spin-dependent interaction of the helical Dirac fermions with light, which originates from the strong spin-orbit coupling in the material. Our results illustrate unusual scenarios in which the spin polarization of photoelectrons is completely different from the spin state of electrons in the originating initial states. The results also provide the basis for a novel source of highly spin-polarized electrons with tunable polarization in three dimensions.

24 pages, 9 Figures. To appear in Nature Physics

References in corpus (11)

• Non-Abelian Anyons and Topological Quantum Computation
• Superconducting proximity effect and Majorana fermions at the surface of a topological insulator
• Discovery (theoretical prediction and experimental observation) of a large-gap topological-insulator class with spin-polarized single-Dirac-cone on the surface
• Topological Field Theory of Time-Reversal Invariant Insulators
• First direct observation of Spin-textures in Topological Insulators : Spin-resolved ARPES as a probe of topological quantum spin Hall effect and Berry's phase
• Topological Surface States Protected From Backscattering by Chiral Spin Texture
• Three dimensional topological invariants for time reversal invariant Hamiltonians and the three dimensional quantum spin Hall effect
• Emergent quantum confinement at topological insulator surfaces
• Direct Measurement of the Out-of-Plane Spin Texture in the Dirac Cone Surface State of a Topological Insulator
• Nonlinear optical probe of tunable surface electrons on a topological insulator
• Spin Polarization of Photoelectrons from Topological Insulators

Cited by in corpus (86)

• Colloquium: Topological Band Theory
• Observation of topological superconductivity on the surface of an iron-based superconductor
• Electronic structure of quantum materials studied by angle-resolved photoemission spectroscopy
• Room temperature magnetization switching in topological insulator-ferromagnet heterostructures by spin-orbit torques
• Surface electronic structure of the topological Kondo insulator candidate correlated electron system SmB6
• Light-induced emergent phenomena in 2D materials and topological materials
• Ultrafast helicity control of surface currents in topological insulators with near-unity fidelity
• Angle-resolved photoemission spectroscopy
• Electrical injection and detection of spin-polarized currents in topological insulator Bi2Te2Se
• Spin polarization and texture of the Fermi arcs in the Weyl Fermion semimetal TaAs
• Dirac cone with helical spin polarization in ultrathin $\alpha$-Sn(001) films
• Dirac Fermions in Antiferromagnetic FeSn Kagome Lattices with Combined Space Inversion and Time Reversal Symmetry
• Selective probing of hidden spin-polarized states in inversion-symmetric bulk MoS2
• Photoelectron spin-polarization-control in the topological insulator Bi2Se3
• Spin-Polarized Surface Resonances Accompanying Topological Surface State Formation
• Photoemission of Bi${}_2$Se${}_3$ with Circularly Polarized Light: Probe of Spin Polarization or Means for Spin Manipulation?
• Helicity dependent photocurrent in electrically gated (Bi,Sb)_2Te_3 thin films
• Orbital-Selective Spin Texture and its Manipulation in a Topological Insulator
• Mapping the chemical potential dependence of current-induced spin polarization in a topological insulator
• Observation of spin-momentum locked surface states in amorphous Bi${}_2$Se${}_3$
• Band resolved imaging of photocurrent in a topological insulator
• Ultrafast spin polarization control of Dirac fermions in topological insulators
• A first principles TDDFT framework for spin and time-resolved ARPES in periodic systems
• Generation of Transient Photocurrents in the Topological Surface State of Sb${}_2$Te${}_3$ by Direct Optical Excitation with Mid-Infrared Pulses
• Relationship between Fermi-Surface Warping and Out-of-Plane Spin Polarization in Topological Insulators: a View from Spin-Resolved ARPES
• Momentum resolved spin dynamics of bulk and surface excited states in the topological insulator $\mathrm{B}{\mathrm{i}}_2\mathrm{S}{\mathrm{e}}_3$
• Magnetic proximity effect at Bi${}_2$Se${}_3$/EuS interface with broken inversion symmetry
• Disorder enabled band structure engineering of a topological insulator surface
• Quasi-particle evidence for the nematic state above $T_{\mathrm{c}}$ in Sr${}_x$Bi${}_2$Se${}_3$
• Anisotropic effect of warping on the lifetime broadening of topological surface states in angle-resolved photoemission from Bi${}_2$Te${}_3$
• Oscillatory surface dichroism of an insulating topological insulator Bi2Te2Se
• Rashba spin splitting of L-gap surface states on Ag(111) and Cu(111)
• Ultrafast Energy- and Momentum-resolved Surface Dirac Photocurrents in the Topological Insulator Sb${}_2$Te${}_3$
• Strong Linear Dichroism in Spin-Polarized Photoemission from Spin-Orbit-Coupled Surface States
• Coherent control over three-dimensional spin polarization for the spin-orbit coupled surface state of Bi${}_2$Se${}_3$
• Gate-tunable transport properties of in-situ capped Bi${}_2$Te${}_3$ topological insulator thin films
• Spin- and angle-resolved photoemission on topological materials
• Electronic structure of YbB${}_6$: Is it a Topological Insulator or not?
• Parallel spin-momentum locking in a chiral topological semimetal
• Topological phase diagram and saddle point singularity in a tunable topological crystalline insulator
• Revealing the ultrafast light-to-matter energy conversion before heat diffusion in a layered Dirac semimetal
• Photogalvanic effect in HgTe/CdTe topological insulator due to edge-bulk optical transitions
• Helicity dependent photovoltaic effect in Bi2Se3 under normal incident light
• Josephson supercurrent in a topological insulator without a bulk shunt
• Photoemission Circular Dichroism and Spin Polarization of the Topological Surface States in Ultrathin Bi2Te3 Films
• Quantum spin Hall insulators in centrosymmetric thin films composed from topologically trivial BiTeI trilayers
• Spin-texture induced by oxygen vacancies in Strontium perovskites (001) surfaces: A theoretical comparison between SrTiO3 and SrHfO3
• Quantum Transport and Potential of Topological States for Thermoelectricity in Bi${}_2$Te${}_3$ Thin Films
• Fundamentally fastest optical processes at the surface of a topological insulator
• Realization of bulk insulating property and carrier manipulation in reversible spin current regime of the ideal topological insulator TlBiSe2
• Synchrotron radiation induced magnetization in magnetically-doped and pristine topological insulators
• Mechanically-controlled spin-selective transport
• Unconventional Spintronics from Chiral Perovskites
• Time-, spin-, and angle-resolved photoemission spectroscopy with a 1-MHz 10.7-eV pulse laser
• Spin-conserving and reversing photoemission from the surface states of Bi${}_2$Se${}_3$ and Au (111)
• Orbit- and Atom-Resolved Spin Textures of Intrinsic, Extrinsic and Hybridized Dirac Cone States
• Electrostatical formation of the Majorana quasiparticles in the quantum dot--nanoring structure
• Electrical detection of spin-polarized current in topological insulator Bi1.5Sb0.5Te1.7Se1.3
• Effects of spin-orbit coupling on the optical response of a material
• Band structure of topological insulators from noise measurements in tunnel junctions
• Exchange-Driven Intermixing of Bulk and Topological Surface State by Chiral Excitons in Bi2Se3
• Discovery of highly spin-polarized conducting surface states in the strong spin-orbit coupling semiconductor Sb${}_2$Se${}_3$
• Electronic correlation determining correlated plasmons in Sb-doped Bi${}_2$Se${}_3$
• $d_{xz/yz}$ Orbital Subband Structures and Chiral Orbital Angular Momentum in the (001) Surface States of SrTiO${}_3$
• Development of a Laser-based angle-resolved-photoemission spectrometer with sub-micrometer spatial resolution and high-efficiency spin detection
• Surface Step Defect in 3D Topological Insulators: Electric Manipulation of Spin and Quantum Spin Hall Effect
• Experimental observation and spin texture of Dirac node arcs in tetradymite topological metals
• Momentum-dependent spin selection rule in photoemission with glide symmetry
• Pseudo-Spin, Real-Spin and Spin Polarization of Photo-emitted Electrons
• Spectroscopic evidence for a new type of surface resonance at noble metal surfaces
• The anomalous spin texture as the probe for interactions in $B{i}_{2-y}S{b}_{y}S{e}_{x}T{e}_{3-x}$
• Strong and Weak Three-Dimensional Topological Insulators Probed by Surface Science Methods
• Altermagnetism, ARPES, symmetry, non-relativistic band splitting
• Photoionization of Xe and Rn from the relativistic random-phase theory
• Visualization of optical polarization transfer to photoelectron spin vector emitted from the spin-orbit coupled surface state
• Observation of Dirac-like surface state bands on the top surface of BiSe
• Spin-polarized quasi 1D state with finite bandgap on the Bi/InSb(001) surface
• Reconstructing the wavefunction of magnetic topological insulators MnBi2Te4 and MnBi4Te7 using spin-resolved photoemission
• Topological spin textures in electronic non-Hermitian systems
• Spin texture tunability in Mn${}_{1-x}$Ge${}_x$Bi${}_2$Te${}_4$ through varying Ge Concentration
• Interaction Approach to Anomalous Spin Texture in Warped Topological Insulators
• Lippmann-Schwinger Approach for Accurate Photoelectron Wavefunctions and Angle-Resolved Photoemission Spectra from First Principles
• An experimental algorithm for identifying the topological nature of Kondo and mixed valence insulators
• Vanishing of interband light absorption in a persistent spin helix state
• Hedgehog-like spin texture in Sb-doped MnBi${}_2$Te${}_4$
• Floquet spin textures in optically pumped non-Hermitian surface states