Topological Edge States with Zero Hall Conductivity in a Dimerized Hofstadter Model
Mesoscale and Nanoscale Physics
2015-11-30 v2
Abstract
The Hofstadter model is a simple yet powerful Hamiltonian to study quantum Hall physics in a lattice system, manifesting its essential topological states. Lattice dimerization in the Hofstadter model opens an energy gap at half filling. Here we show that even if the ensuing insulator has a Chern number equal to zero, concomitantly a doublet of edge states appear that are pinned at specific momenta. We demonstrate that these states are topologically protected by inversion symmetry in specific one-dimensional cuts in momentum space, define and calculate the corresponding invariants and identify a platform for the experimental detection of these novel topological states.
Keywords
Cite
@article{arxiv.1510.08651,
title = {Topological Edge States with Zero Hall Conductivity in a Dimerized Hofstadter Model},
author = {Alexander Lau and Carmine Ortix and Jeroen van den Brink},
journal= {arXiv preprint arXiv:1510.08651},
year = {2015}
}
Comments
5 pages, 3 figures + Supplemental Material (6 pages)