Dirac cone shift of a passivated topological Bi2Se3 interface state

Abstract

Gated terahertz cyclotron resonance measurements on epitaxial Bi2Se3 thin films capped with In2Se3 enable the first spectroscopic characterization of a single topological interface state from the vicinity of the Dirac point to above the conduction band edge. A precipitous drop in the scattering rate with Fermi energy is observed that is interpreted as the surface state decoupling from bulk states and evidence of a shift of the Dirac point towards mid-gap. Near the Dirac point, potential fluctuations of 50 meV are deduced from an observed loss of differential optical spectral weight near the Dirac point. Potential fluctuations are reduced by a factor of two at higher surface Fermi levels in the vicinity of the conduction band edge inferred from the width of the scattering rate step. The passivated topological interface state attains a high mobility of 3500 cm2/Vsec near the Dirac point.

12 Pages, 6 figures

References in corpus (33)

• Topological Insulators
• Topological insulators and superconductors
• Discovery (theoretical prediction and experimental observation) of a large-gap topological-insulator class with spin-polarized single-Dirac-cone on the surface
• Electronic transport in two dimensional graphene
• Topological Field Theory of Time-Reversal Invariant Insulators
• Charged Impurity Scattering in Graphene
• Topological Surface States Protected From Backscattering by Chiral Spin Texture
• Hexagonal Warping Effects in the Surface States of Topological Insulator Bi${}_2$Te${}_3$
• Topological origin of subgap conductance in insulating bilayer graphene
• Two-dimensional Dirac fermions in a topological insulator: transport in the quantum limit
• Drude Conductivity of Dirac Fermions in Graphene
• Coexistence of the topological state and a two-dimensional electron gas on the surface of Bi2Se3
• Bulk Fermi surface coexistence with Dirac surface state in Bi${}_2$Se${}_3$: a comparison of photoemission and Shubnikov-de Haas measurements
• Bulk Band Gap and Surface State Conduction Observed in Voltage-Tuned Crystals of the Topological Insulator Bi${}_2$Se${}_3$
• Strong surface scattering in ultrahigh mobility Bi2Se3 topological insulator crystals
• Landau Quantization of Massless Dirac Fermions in Topological Insulator
• Surface conduction of topological Dirac electrons in bulk insulating Bi2Se3
• Thickness-independent transport channels in topological insulator Bi2Se3 thin films
• Rapid Surface Oxidation as a Source of Surface Degradation Factor for Bi2Se3
• Spatial Fluctuations of Helical Dirac Fermions on the Surface of Topological Insulators
• Surface State Transport and Ambipolar Electric Field Effect in Bi2Se3 Nanodevices
• Momentum-Resolved Landau-Level Spectroscopy of Dirac Surface State in Bi2Se3
• Topological quantization in units of the fine structure constant
• THz response and colossal Kerr rotation from the surface states of the topological insulator Bi${}_2$Se${}_3$
• Epitaxial growth of topological insulator Bi2Se3 film on Si(111) with atomically sharp interface
• Topological-Metal to Band-Insulator Transition in (Bi1-xInx)2Se3 Thin Films
• Rashba spin-splitting control at the surface of the topological insulator Bi2Se3
• Angular-dependent oscillations of the magnetoresistance in Bi_2Se_3 due to the three-dimensional bulk Fermi surface
• Two-dimensional surface charge transport in topological insulators
• Far infrared cyclotron resonance and Faraday effect in Bi2Se3
• Terahertz Kerr and Reflectivity Measurements on the Topological Insulator Bi2Se3
• Simultaneous measurement of circular dichroism and Faraday rotation at terahertz frequencies using heterodyne detection
• Electrostatic effects and band-bending in doped topological insulators

Cited by in corpus (15)

• High-Resolution Faraday Rotation and Electron-Phonon Coupling in Surface States of the Bulk-Insulating Topological Insulator Cu${}_{0.02}$Bi${}_2$Se${}_3$
• Optical evidence of surface state suppression in Bi based topological insulators
• Signature of a topological phase transition in the Josephson supercurrent through a topological insulator
• Gate-tunable transport properties of in-situ capped Bi${}_2$Te${}_3$ topological insulator thin films
• Gate-Variable Mid-Infrared Optical Transitions in a $(B{i}_{1-x}S{b}_x{)}_{2}T{e}_3$ Topological Insulator
• Observation of Ultrahigh Mobility Surface States in a Topological Crystalline Insulator by Infrared Spectroscopy
• Strong interband Faraday rotation in 3D topological insulator Bi2Se3
• Modeling Near-Surface Bound Electron States in Three-Dimensional Topological Insulator: Analytical and Numerical Approaches
• Band bending at the surface of Bi${}_2$Se${}_3$ studied from first principles
• Optical investigation of thermoelectric topological crystalline insulator Pb${}_{0.77}$Sn${}_{0.23}$Se
• Josephson Effect and Charge Distribution in Thin Bi${}_2$Te${}_3$ Topological Insulators
• Resonant Faraday and Kerr effects due to in-gap states on the surface of a topological insulator
• Cyclotron Resonance in Topological Insulators: Non-Relativistic Effects
• A new type of cyclotron resonance from charge-impurity scattering in the bulk-insulating Bi${}_2$Se${}_3$ thin films
• Large Enhancement of Electronic Thermal Conductivity and Lorenz Number in Topological Insulator Bi2Te2Se Thin Films