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arXiv · 1708.07099

Intrinsic two-dimensional state on the pristine surface of tellurium

Pengke Li·Ian Appelbaum
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Abstract

Using a tight-binding description, we show how the zero-dimensional state bound to the edge of a single one-dimensional helical chain of tellurium atoms evolves into two-dimensional states on the c-axis surface of the three-dimensional trigonal bulk. We give an effective Hamiltonian description of its dispersion in k-space by exploiting confinement to a virtual bilayer, and elaborate on the diminished role of spin-orbit coupling. These previously-unidentified intrinsic gap-penetrating surface bands were neglected in the interpretation of seminal experiments, where two-dimensional transport was otherwise attributed to extrinsic accumulation layers.

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Pengke Li, Ian Appelbaum. 2017-08-23. Intrinsic two-dimensional state on the pristine surface of tellurium. https://doi.org/10.1103/physrevb.97.201402

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