New interpretation of the origin of 2DEG states at the surface of layered topological insulators

Abstract

On the basis of relativistic ab-initio calculations we show that the driving mechanism of simultaneous emergence of parabolic and M-shaped 2D electron gas (2DEG) bands at the surface of layered topological insulators as well as Rashba-splitting of the former states is an expansion of van der Waals (vdW) spacings caused by intercalation of metal atoms or residual gases. The expansion of vdW spacings and emergence of the 2DEG states localized in the (sub)surface region are also accompanied by a relocation of the topological surface state to the lower quintuple layers, that can explain the absence of interband scattering found experimentally.

5 pages, 4 figures

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Cited by in corpus (26)

• Hedgehog Spin-texture and Berry's Phase tuning in a Magnetic Topological Insulator
• Emergent quantum confinement at topological insulator surfaces
• Persistence of Topological Order and Formation of Quantum Well States in Topological Insulators Bi2(Se,Te)3 under Ambient Conditions
• Evidence for a direct band gap in the topological insulator Bi2Se3 from theory and experiment
• Nonmagnetic band gap at the Dirac point of the magnetic topological insulator (Bi${}_{1-x}$Mn${}_x{)}_2$Se${}_3$
• Analytical solution for the surface states of antiferromagnetic topological insulator MnBi${}_2$Te${}_4$
• Routes to realize the axion-insulator phase in MnBi${}_2$Te${}_4$(Bi${}_2$Te${}_3$)${}_n$ family: a perspective
• Distinct magnetic gaps between antiferromagnetic and ferromagnetic orders driven by surface defects in the topological magnet MnBi2Te4
• Observation of Distinct Bulk and Surface Chemical Environments in a Topological Insulator under Magnetic doping
• Floquet engineering of magnetic topological insulator MnBi${}_2$Te${}_4$ films
• Observation of quantum oscillations in FIB fabricated nanowires of topological insulator (Bi2Se3)
• Dirac states with knobs on: interplay of external parameters and the surface electronic properties of 3D topological insulators
• Probing Dirac Fermion Dynamics in Topological Insulator Bi${}_2$Se${}_3$ Films with Scanning Tunneling Microscope
• Modeling Near-Surface Bound Electron States in Three-Dimensional Topological Insulator: Analytical and Numerical Approaches
• New topological surface state in layered topological insulators: unoccupied Dirac cone
• Spin-Polarized Quantum Well States on Bi${}_{2-x}$Fe${}_x$Se${}_3$
• Three-Dirac-fermion approach to unexpected universal gapless surface states of van der Waals magnetic topological insulators
• Experimental search for one-dimensional edge states at surface steps of the topological insulator Bi${}_2$Se${}_3$: Distinguishing between effects and artifacts
• Low coverage surface diffusion in complex energy landscapes: Analytical solution and application to intercalation in topological insulators
• Nature of the Dirac gap modulation and surface magnetic interaction in axion antiferromagnetic topological insulator MnBi${}_2$Te${}_4$
• Interplay between exchange split Dirac and Rashba-type surface states in MnBi${}_2$Te${}_4$/BiTeI interface
• Numerical analysis of surface and edge states in slabs, stripes, rods and surface steps of topological insulators
• Twin Domain Structure in Magnetically Doped Topological Insulators
• Pyridine intercalated Bi${}_2$Se${}_3$ heterostructures: controlling the topologically protected states
• Interplay between surface Dirac and Rashba states specific for topologically nontrivial van der Waals superlattices
• Quantized one-dimensional edge channels with strong spin-orbit coupling in 3D topological insulators