• Featured in Physics
  • Editors' Suggestion

Failure of Conductance Quantization in Two-Dimensional Topological Insulators due to Nonmagnetic Impurities

Pietro Novelli, Fabio Taddei, Andre K. Geim, and Marco Polini
Phys. Rev. Lett. 122, 016601 – Published 2 January 2019
Physics logo See Synopsis: Interrupting Flow in a 2D Topological Insulator
PDFHTMLExport Citation

Abstract

Despite topological protection and the absence of magnetic impurities, two-dimensional topological insulators display quantized conductance only in surprisingly short channels, which can be as short as 100 nm for atomically thin materials. We show that the combined action of short-range nonmagnetic impurities located near the edges and on site electron-electron interactions effectively creates noncollinear magnetic scatterers, and, hence, results in strong backscattering. The mechanism causes deviations from quantization even at zero temperature and for a modest strength of electron-electron interactions. Our theory provides a straightforward conceptual framework to explain experimental results, especially those in atomically thin crystals, plagued with short-range edge disorder.

  • Figure
  • Figure
  • Figure
  • Figure
  • Received 16 July 2018

DOI:https://doi.org/10.1103/PhysRevLett.122.016601

© 2019 American Physical Society

Physics Subject Headings (PhySH)

Condensed Matter, Materials & Applied Physics

Synopsis

Key Image

Interrupting Flow in a 2D Topological Insulator

Published 2 January 2019

Theorists predict that backscattering of electrons by nonmagnetic impurities can disrupt current flow in a 2D topological insulator, in agreement with experiments.

See more in Physics

Authors & Affiliations

Pietro Novelli1,2,*, Fabio Taddei3, Andre K. Geim4, and Marco Polini1,4

  • 1Istituto Italiano di Tecnologia, Graphene Labs, Via Morego 30, I-16163 Genova, Italy
  • 2NEST, Scuola Normale Superiore, I-56126 Pisa, Italy
  • 3NEST, Istituto Nanoscienze-CNR and Scuola Normale Superiore, I-56126 Pisa, Italy
  • 4School of Physics and Astronomy, University of Manchester, Oxford Road, Manchester M13 9PL, United Kingdom

  • *pietro.novelli@sns.it

Article Text (Subscription Required)

Click to Expand

Supplemental Material (Subscription Required)

Click to Expand

References (Subscription Required)

Click to Expand
Issue

Vol. 122, Iss. 1 — 11 January 2019

Reuse & Permissions
Access Options
Author publication services for translation and copyediting assistance advertisement

Authorization Required


×
×

Images

×

Sign up to receive regular email alerts from Physical Review Letters

Log In

Cancel
×

Search


Article Lookup

Paste a citation or DOI

Enter a citation
×