Tailoring the topological surface state in ultrathin $\alpha$-Sn (111) films

Abstract

We report on the electronic structure of $\alpha$-Sn films in the very low thickness regime grown on InSb(111)A. High-resolution low photon energies angle-resolved photoemission (ARPES) allows for the direct observation of the linearly dispersing 2D topological surface states (TSSs) that exist between the second valence band and the conduction band. The Dirac point of this TSS was found to be 200meV below the Fermi level in 10-nm-thick $\alpha$-Sn films, which enables the observation of the hybridization gap opening at the Dirac point of the TSS for thinner films. The crossover to a quasi-2D electronic structure is accompanied by a full gap opening at the Brillouin zone center, in agreement with our density functional theory calculations. We further identify the thickness regime of $\alpha$-Sn films where the hybridization gap in TSS coexists with the topologically non-trivial electronic structure and one can expect the presence of a 1D helical edge states.

arXiv comment7 pages, 5 figures, 1 table

References in corpus (23)

• Quantum Spin Hall Effect and Topological Phase Transition in HgTe Quantum Wells
• Quantum Spin Hall Insulator State in HgTe Quantum Wells
• Topological Insulators with Inversion Symmetry
• Epitaxial Growth of Two-Dimensional Stanene
• Bismuthene on a SiC Substrate: A Candidate for a New High-Temperature Quantum Spin Hall Paradigm
• Tunable Multifunctional Topological Insulators in Ternary Heusler Compounds
• Oscillatory crossover from two dimensional to three dimensional topological insulators
• Spin-pumping into surface states of topological insulator α-Sn, spin to charge conversion at room temperature
• Anomalous Finite Size Effects on Surface States in the Topological Insulator Bi${}_2$Se${}_3$
• Superconductivity in Few-Layer Stanene
• Surface States of Topological Insulators
• Elemental Topological Insulator with a Tunable Fermi Level: Strained α-Sn on InSb(001)
• Elemental topological Dirac semimetal: α-Sn on InSb(111)
• Dirac cone with helical spin polarization in ultrathin $\alpha$-Sn(001) films
• Gapped Electronic Structure of Epitaxial Stanene on InSb(111)
• Strain-Induced Band Engineering in Monolayer Stanene on Sb(111)
• Tensile Strained Gray Tin: a New Dirac Semimetal for Observing Negative Magnetoresistance with Shubnikov-de-Haas Oscillation
• ARPES and transport studies of the elemental topological insulator $\alpha$-Sn
• The topological surface state of $\alpha$-Sn on InSb(001) as studied by photoemission
• Double Band Inversion in $\alpha$-Sn: Appearance of Topological Surface States and the Role of Orbital Composition
• Growth and Magnetotransport in Thin Film α-Sn on CdTe
• Interplay of Dirac nodes and Volkov-Pankratov surface states in compressively strained HgTe
• Quantum Spin Hall Insulators in Tin Films: Beyond Stanene

Cited by in corpus (4)

• Structural and electronic properties of the pure and stable elemental 3D topological Dirac semimetal $\alpha$-Sn
• First Principles Assessment of CdTe as a Tunnel Barrier at the $\alpha$-Sn/InSb Interface
• Decagonal Sn clathrate on $d$-Al-Ni-Co
• 3D Topological Semimetal Phases of Strained $\alpha$-Sn on Insulating Substrate