Multiple flat bands and topological Hofstadter butterfly in twisted bilayer graphene close to the second magic angle

Abstract

Multiple flat bands in high-quality twisted bilayer graphene close to the theoretically predicted second magic angle are observed. These well-isolated flat moiré bands host a nontrivial topology which is evidenced by a connecting multiband Hofstadter butterfly spectrum. This work provides a perspective for understanding the emergent quantum phases (i.e., strong correlation and band topology) in twisted bilayer graphene and the fractal Hofstadter spectra of multiple topological bands.

Document Details

Document Type
Pub Defense Publication
Publication Date
Jul 23, 2021
Source ID
10.1073/pnas.2100006118

Entities

People

  • Allan H. MacDonald
  • Andrei Bernevig
  • B. A. Piot
  • Biao Lian
  • Dmitri K. Efetov
  • Gaurav Chaudhary
  • Giulio Romagnoli
  • Kenji Watanabe
  • Martino Poggio
  • Takashi Taniguchi
  • Xiaobo Lu

Organizations

  • Barcelona Institute for Science and Technology
  • Consejería de Economía y Hacienda
  • Generalitat of Catalonia
  • Grenoble Alpes University
  • National Institute for Materials Science
  • Office of Basic Energy Sciences
  • Office of Naval Research Global
  • Princeton University
  • Simons Foundation
  • Swiss National Science Foundation
  • University of Basel
  • University of Texas at Austin

Tags

Fields of Study

  • Physics

Readers

  • Quantum Dot Semiconductor Device Photonics and Graphene Optoelectronic Materials and THz Physics.

Technology Areas

  • Microelectronics
  • Microelectronics - Graphene
  • Quantum Computing