Related Experiment Video
Updated: May 7, 2026

Experimental Methods for Spin- and Angle-Resolved Photoemission Spectroscopy Combined with Polarization-Variable Laser
Published on: June 28, 2018
Hierarchy of fractional Chern insulators and competing compressible states
A M Läuchli1, Zhao Liu, E J Bergholtz
1Institut für Theoretische Physik, Universität Innsbruck, A-6020 Innsbruck, Austria and Max-Planck-Institut für Physik komplexer Systeme, Nöthnitzer Straße 38, D-01187 Dresden, Germany.
Abstract:
We study the phase diagram of interacting electrons in a dispersionless Chern band as a function of their filling. We find hierarchy multiplets of incompressible states at fillings ν = 1/3, 2/5, 3/7, 4/9, 5/9, 4/7, 3/5 as well as ν = 1/5, 2/7. These are accounted for by an analogy to Haldane pseudopotentials extracted from an analysis of the two-particle problem. Important distinctions to standard fractional quantum Hall physics are striking: in the absence of particle-hole symmetry in a single band, an interaction-induced single-hole dispersion appears, which perturbs and eventually destabilizes incompressible states as ν increases. For this reason, the nature of the state at ν = 2/3 is hard to pin down, while ν = 5/7, 4/5 do not seem to be incompressible in our system.
Related Concept Videos
States of Matter and Phase Changes
Comparing Intermolecular Forces: Melting Point, Boiling Point, and Miscibility
Temporary attractive forces like dispersion are present in all molecules, whether they are polar or nonpolar. They...
Metallic Solids
All metallic solids exhibit high thermal and electrical conductivity, metallic luster, and malleability. Many...
Fermi Level
At absolute zero temperature, electrons fill all energy states up to the Fermi level, leaving upper states empty. As the temperature rises,...
Imperfections in Crystal Structure: Stoichiometric Point Defects
Phase Transitions: Sublimation and Deposition
