Topological metal behavior in GeBi2Te4 single crystals

Abstract

The metallic character of the GeBi2Te4 single crystals is probed using a combination of structural and physical properties measurements, together with density functional theory (DFT) calculations. The structural study shows distorted Ge coordination polyhedra, mainly of the Ge octahedra. This has a major impact on the band structure, resulting in bulk metallic behavior of GeBi2Te4, as indicated by DFT calculations. Such calculations place GeBi2Te4 in a class of a few known non-trivial topological metals, and explains why an observed Dirac point lies below the Fermi energy at about -0.12eV. A topological picture of GeBi2Te4 is confirmed by the observation of surface state modulations by scanning tunneling microscopy (STM).

10 pages, 8 figures

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Cited by in corpus (5)

• Colloquium: Topological Band Theory
• Detailed structural and topological analysis of SnBi2Te4 single crystal
• Unconventional topological phase transition from semimetal to insulator in SnBi2Te4: Role of anomalous thermal expansion
• Intrinsic surface dipole in topological insulators
• Observation of a Smoothly Tunable Dirac Point in $Ge(B{i}_{x}S{b}_{1-x}{)}_{2}T{e}_4$