%0 Journal Article
%T Topological Edge States with Zero Hall Conductivity in a Dimerized Hofstadter Model
%A Alexander Lau
%A Carmine Ortix
%A Jeroen van den Brink
%J Physics
%D 2015
%I arXiv
%R 10.1103/PhysRevLett.115.216805
%X 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.
%U http://arxiv.org/abs/1510.08651v2