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arXiv · 1905.03484

Higher-order Topological Mott Insulators

Koji Kudo·Tsuneya Yoshida·Yasuhiro Hatsugai
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Abstract

We propose a new correlated topological state which we call a higher-order topological Mott insulator (HOTMI). This state exhibits a striking bulk-boundary correspondence due to electron correlations. Namely, the topological properties in the bulk, characterized by the Z3 spin-Berry phase, result in gapless corner modes emerging only in spin excitations (i.e., the single-particle excitations remain gapped around the corner). We demonstrate the emergence of the HOTMI in a Hubbard model on the kagome lattice, and elucidate how strong correlations change gapless corner modes at the noninteracting case.

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Koji Kudo, Tsuneya Yoshida, Yasuhiro Hatsugai. 2019-05-09. Higher-order Topological Mott Insulators. https://doi.org/10.1103/physrevlett.123.196402

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