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arXiv · 1410.2001

$\mathbb Z_2$ slave-spin theory of a strongly correlated Chern insulator

Diana Prychynenko·Sebastian D. Huber
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Abstract

We calculate the phase diagram of the topological honeycomb model in the presence of strong interactions. We concentrate on half filling and employ a ${\mathbb Z}_{2}$ slave-spin method to find a band insulator with staggered density, a spin-density-wave and a Mott insulating phase. Both the band insulator and the spin-density wave come in various topological varieties. Finally, we calculate the response function relevant for lattice modulation spectroscopy with cold atomic gases in optical lattices.

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Diana Prychynenko, Sebastian D. Huber. 2014-10-08. $\mathbb Z_2$ slave-spin theory of a strongly correlated Chern insulator. https://doi.org/10.1016/j.physb.2015.10.027

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