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Engineering Dirac electrons emergent on the surface of a topological insulator.

ABSTRACT: The concept of the topological insulator (TI) has introduced a new point of view to condensed-matter physics, relating a priori unrelated subfields such as quantum (spin, anomalous) Hall effects, spin-orbit coupled materials, some classes of nodal superconductors, superfluid 3He, etc. From a technological point of view, TIs are expected to serve as platforms for realizing dissipationless transport in a non-superconducting context. The TI exhibits a gapless surface state with a characteristic conic dispersion (a surface Dirac cone). Here, we review peculiar finite-size effects applicable to such surface states in TI nanostructures. We highlight the specific electronic properties of TI nanowires and nanoparticles, and in this context we contrast the cases of weak and strong TIs. We study the robustness of the surface and the bulk of TIs against disorder, addressing the physics of Dirac and Weyl semimetals as a new research perspective in the field.

SUBMITTER: Yoshimura Y

PROVIDER: S-EPMC5036486 | biostudies-literature | 2015 Feb

REPOSITORIES: biostudies-literature

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Engineering Dirac electrons emergent on the surface of a topological insulator.

Yoshimura Yukinori Y Kobayashi Koji K Ohtsuki Tomi T Imura Ken-Ichiro KI

Science and technology of advanced materials 20150116 1

The concept of the topological insulator (TI) has introduced a new point of view to condensed-matter physics, relating <i>a priori</i> unrelated subfields such as quantum (spin, anomalous) Hall effects, spin-orbit coupled materials, some classes of nodal superconductors, superfluid <sup>3</sup>He, etc. From a technological point of view, TIs are expected to serve as platforms for realizing dissipationless transport in a non-superconducting context. The TI exhibits a gapless surface state with a ...[more]

PMID: 27877741

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