Topological Invariant and Quantum Spin Models from Magnetic \pi\ Fluxes in Correlated Topological Insulators
| Autor: | M. Bercx, Fakher F. Assaad, Martin Hohenadler |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2012 |
| Předmět: |
Physics
Quantum Physics Condensed matter physics QC1-999 General Physics and Astronomy Condensed Matter - Strongly Correlated Electrons Simple (abstract algebra) Topological insulator State of matter Strongly correlated material ddc:530 Condensed Matter::Strongly Correlated Electrons Invariant (mathematics) Spin (physics) |
| Zdroj: | Physical Review X, Vol 3, Iss 1, p 011015 (2013) |
| Popis: | 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 spinon 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 spinons. \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. Due to 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. Comment: 12 pages, 12 figures, published version |
| Databáze: | OpenAIRE |
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