• Featured in Physics
  • Editors' Suggestion

Quantum Spin Hall States and Topological Phase Transition in Germanene

Pantelis Bampoulis, Carolien Castenmiller, Dennis J. Klaassen, Jelle van Mil, Yichen Liu, Cheng-Cheng Liu, Yugui Yao, Motohiko Ezawa, Alexander N. Rudenko, and Harold J. W. Zandvliet
Phys. Rev. Lett. 130, 196401 – Published 12 May 2023
Physics logo See synopsis: Quantum Spin Hall Effect Seen in Graphene Analog
PDFHTMLExport Citation

Abstract

We present the first experimental evidence of a topological phase transition in a monoelemental quantum spin Hall insulator. Particularly, we show that low-buckled epitaxial germanene is a quantum spin Hall insulator with a large bulk gap and robust metallic edges. Applying a critical perpendicular electric field closes the topological gap and makes germanene a Dirac semimetal. Increasing the electric field further results in the opening of a trivial gap and disappearance of the metallic edge states. This electric field-induced switching of the topological state and the sizable gap make germanene suitable for room-temperature topological field-effect transistors, which could revolutionize low-energy electronics.

  • Figure
  • Figure
  • Received 9 November 2022
  • Accepted 24 March 2023

DOI:https://doi.org/10.1103/PhysRevLett.130.196401

© 2023 American Physical Society

Physics Subject Headings (PhySH)

Condensed Matter, Materials & Applied Physics

synopsis

Key Image

Quantum Spin Hall Effect Seen in Graphene Analog

Published 12 May 2023

Germanene undergoes a topological phase transition and then becomes a normal insulator when the strength of an applied electric field is dialed up.

See more in Physics

Authors & Affiliations

Pantelis Bampoulis1,*, Carolien Castenmiller1, Dennis J. Klaassen1, Jelle van Mil1, Yichen Liu2, Cheng-Cheng Liu2, Yugui Yao2, Motohiko Ezawa3, Alexander N. Rudenko4, and Harold J. W. Zandvliet1

  • 1Physics of Interfaces and Nanomaterials, MESA+ Institute, University of Twente, Drienerlolaan 5, 7522 NB, Enschede, Netherlands
  • 2Centre for Quantum Physics, Key Laboratory of Advanced Optoelectronic Quantum Architecture and Measurement (MOE), School of Physics, Beijing Institute of Technology, Beijing 100081, China
  • 3Department of Applied Physics, University of Tokyo, Hongo, 113-8656 Tokyo, Japan
  • 4Institute for Molecules and Materials, Radboud University Nijmegen, Heyendaalseweg 135, 6525 AJ Nijmegen, Netherlands

  • *p.bampoulis@utwente.nl

Article Text (Subscription Required)

Click to Expand

Supplemental Material (Subscription Required)

Click to Expand

References (Subscription Required)

Click to Expand
Issue

Vol. 130, Iss. 19 — 12 May 2023

Reuse & Permissions
Access Options
CHORUS

Article part of CHORUS

Accepted manuscript will be available starting 11 May 2024.
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
×