@article{AssaadBercxHohenadler2013,
  author    = {Assaad, F. F. and Bercx, M. and Hohenadler, M.},
  title     = {Topological Invariant and Quantum Spin Models from Magnetic pi Fluxes in Correlated Topological Insulators},
  series = {Physical Review X},
  volume    = {3},
  journal   = {Physical Review X},
  number    = {1},
  doi       = {10.1103/PhysRevX.3.011015},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-129849},
  year      = {2013},
  abstract  = {The adiabatic insertion of a \(\pi\) flux into a quantum spin Hall insulator gives rise to localized spin and charge fluxon states. We demonstrate that \(\pi\) fluxes can be used in exact quantum Monte Carlo simulations to identify a correlated \(Z_2\) topological insulator using the example of the Kane-Mele-Hubbard model. In the presence of repulsive interactions, a \(\pi\) flux gives rise to a Kramers doublet of spin-fluxon states with a Curie-law signature in the magnetic susceptibility. Electronic correlations also provide a bosonic mode of magnetic excitons with tunable energy that act as exchange particles and mediate a dynamical interaction of adjustable range and strength between spin fluxons. \(\pi\) fluxes can therefore be used to build models of interacting spins. This idea is applied to a three-spin ring and to one-dimensional spin chains. Because of the freedom to create almost arbitrary spin lattices, correlated topological insulators with \(\pi\) fluxes represent a novel kind of quantum simulator, potentially useful for numerical simulations and experiments.},
  language  = {en}
}