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arXiv · 1401.2407

Topological metal behavior in GeBi2Te4 single crystals

A. Marcinkova·J. K. Wang·C. Slavonic·Andriy H. Nevidomskyy·K. F. Kelly·Y. Filinchuk·E. Morosan
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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).

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A. Marcinkova, J. K. Wang, C. Slavonic, Andriy H. Nevidomskyy, K. F. Kelly, Y. Filinchuk, E. Morosan. 2014-01-10. Topological metal behavior in GeBi2Te4 single crystals. https://doi.org/10.1103/physrevb.88.165128

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