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arXiv · 1804.01996

Bilayer Haldane model: From trivial band insulator to fractionalized quantum anomalous Hall insulator

Sopheak Sorn
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Abstract

Motivated by work on the bulk topological proximity effect and the topological bootstrap, we consider two coupled layers of quantum anomalous Hall (QAH) insulators with opposite signs of time-reversal breaking, which leads to a trivial band insulator at half-filling. We study the impact of interactions in this model within slave rotor theory, which leads to a layer-selective Mott transition, resulting in a fractionalized quantum anomalous Hall insulator QAH$^*$ where a Chern band insulator coexists with a chiral spin liquid. We also compute the edge electron spectral function in the vicinity of the QAH$^*$ phase.

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Sopheak Sorn. 2018-04-05. Bilayer Haldane model: From trivial band insulator to fractionalized quantum anomalous Hall insulator. https://doi.org/10.1103/physrevb.98.125145

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