Quantum Spin Hall Effect in IV-VI Topological Crystalline Insulators

Abstract

We envision that quantum spin Hall effect should be observed in $(111)$-oriented thin films of SnSe and SnTe topological crystalline insulators. Using a tight-binding approach supported by first-principles calculations of the band structures we demonstrate that in these films the energy gaps in the two-dimensional band spectrum depend in an oscillatory fashion on the layer thickness. These results as well as the calculated topological invariant indexes and edge state spin polarizations show that for films ~20-40 monolayers thick a two-dimensional topological insulator phase appears. In this range of thicknesses in both, SnSe and SnTe, (111)-oriented films edge states with Dirac cones with opposite spin polarization in their two branches are obtained. While in the SnTe layers a single Dirac cone appears at the projection of the G point of the two-dimensional Brillouin zone, in the SnSe (111)-oriented layers three Dirac cones at M points projections are predicted.

6 pages, 6 figures

References in corpus (10)

• Quantum Spin Hall Insulator State in HgTe Quantum Wells
• Topological Insulators with Inversion Symmetry
• Topological Crystalline Insulators
• Quantum Spin Hall Effect and Topological Field Effect Transistor in Two-Dimensional Transition Metal Dichalcogenides
• Time Reversal Polarization and a Z_2 Adiabatic Spin Pump
• Epitaxial growth of large-gap quantum spin Hall insulator on semiconductor surface
• Tuning phase transition between quantum spin Hall and ordinary insulating phases
• Topological Crystalline Insulator Nanomembrane with Strain-Tunable Band Gap
• Quantum spin Hall effect induced by electric field in silicene
• Electrically Tunable Quantum Spin Hall State in Topological Crystalline Insulator Thin films

Cited by in corpus (5)

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• Electronic properties of SnTe-class topological crystalline insulator materials
• Edge states at nematic domain walls in FeSe films
• Defect-free SnTe topological crystalline insulator nanowires grown by molecular beam epitaxy on graphene
• Fragility of the Dirac Cone Splitting in Topological Crystalline Insulator Heterostructures