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arXiv · 1405.2036

Resolving the Dirac Cone on the Surface of Bi2Te3 Topological Insulator Nanowires by Field-Effect Measurements

Johannes Gooth·Bacel Hamdou·August Dorn·Robert Zierold·Kornelius Nielsch
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Abstract

We validate the linear dispersion relation and resolve the Dirac cone on the surface of a single Bi2Te3 nanowire via a combination of field-effect and magnetoresistance measurements by which we unambiguously prove the topological insulator nature of the nanowire surface states. Moreover we show that the experimentally determined carrier concentration, mobility and cyclotron mass of the surface states are in excellent agreement with relativistic models. Our method provides a facile way to identify topological insulators that too small for angle-resolved photo emission spectroscopy.

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Johannes Gooth, Bacel Hamdou, August Dorn, Robert Zierold, Kornelius Nielsch. 2014-05-08. Resolving the Dirac Cone on the Surface of Bi2Te3 Topological Insulator Nanowires by Field-Effect Measurements. https://doi.org/10.1063/1.4883887

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