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Higher-order topological Mott insulator on the pyrochlore lattice.

ABSTRACT: We provide the first unbiased evidence for a higher-order topological Mott insulator in three dimensions by numerically exact quantum Monte Carlo simulations. This insulating phase is adiabatically connected to a third-order topological insulator in the noninteracting limit, which features gapless modes around the corners of the pyrochlore lattice and is characterized by a [Formula: see text] spin-Berry phase. The difference between the correlated and non-correlated topological phases is that in the former phase the gapless corner modes emerge only in spin excitations being Mott-like. We also show that the topological phase transition from the third-order topological Mott insulator to the usual Mott insulator occurs when the bulk spin gap solely closes.

SUBMITTER: Otsuka Y

PROVIDER: S-EPMC8511174 | biostudies-literature | 2021 Oct

REPOSITORIES: biostudies-literature

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Higher-order topological Mott insulator on the pyrochlore lattice.

Otsuka Yuichi Y Yoshida Tsuneya T Kudo Koji K Yunoki Seiji S Hatsugai Yasuhiro Y

Scientific reports 20211012 1

We provide the first unbiased evidence for a higher-order topological Mott insulator in three dimensions by numerically exact quantum Monte Carlo simulations. This insulating phase is adiabatically connected to a third-order topological insulator in the noninteracting limit, which features gapless modes around the corners of the pyrochlore lattice and is characterized by a [Formula: see text] spin-Berry phase. The difference between the correlated and non-correlated topological phases is that in ...[more]

PMID: 34642375

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