• Featured in Physics

Nearly Flatbands with Nontrivial Topology

Kai Sun, Zhengcheng Gu, Hosho Katsura, and S. Das Sarma
Phys. Rev. Lett. 106, 236803 – Published 6 June 2011
Physics logo See Viewpoint: Fractional quantum Hall effect without Landau levels
PDFHTMLExport Citation

Abstract

We report the theoretical discovery of a class of 2D tight-binding models containing nearly flatbands with nonzero Chern numbers. In contrast with previous studies, where nonlocal hoppings are usually required, the Hamiltonians of our models only require short-range hopping and have the potential to be realized in cold atomic gases. Because of the similarity with 2D continuum Landau levels, these topologically nontrivial nearly flatbands may lead to the realization of fractional anomalous quantum Hall states and fractional topological insulators in real materials. Among the models we discover, the most interesting and practical one is a square-lattice three-band model which has only nearest-neighbor hopping. To understand better the physics underlying the topological flatband aspects, we also present the studies of a minimal two-band model on the checkerboard lattice.

  • Figure
  • Figure
  • Figure
  • Received 28 December 2010

DOI:https://doi.org/10.1103/PhysRevLett.106.236803

© 2011 American Physical Society

Viewpoint

Key Image

Fractional quantum Hall effect without Landau levels

Published 6 June 2011

Researchers develop models that could exhibit a fractional quantum Hall effect in the absence of an external magnetic field.

See more in Physics

Authors & Affiliations

Kai Sun1, Zhengcheng Gu2, Hosho Katsura3, and S. Das Sarma1

  • 1Condensed Matter Theory Center and Joint Quantum Institute, Department of Physics, University of Maryland, College Park, Maryland 20742, USA
  • 2Kavli Institute for Theoretical Physics, University of California, Santa Barbara, California 93106, USA
  • 3Department of Physics, Gakushuin University, Mejiro, Toshima-ku, Tokyo 171-8588, Japan

See Also

High-Temperature Fractional Quantum Hall States

Evelyn Tang, Jia-Wei Mei, and Xiao-Gang Wen
Phys. Rev. Lett. 106, 236802 (2011)

Fractional Quantum Hall States at Zero Magnetic Field

Titus Neupert, Luiz Santos, Claudio Chamon, and Christopher Mudry
Phys. Rev. Lett. 106, 236804 (2011)

Article Text (Subscription Required)

Click to Expand

Supplemental Material (Subscription Required)

Click to Expand

References (Subscription Required)

Click to Expand
Issue

Vol. 106, Iss. 23 — 10 June 2011

Reuse & Permissions
Access Options
CHORUS

Article Available via CHORUS

Download Accepted Manuscript
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
×