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arXiv · 2105.09568

Higher-Order Topological Mott Insulator on the Pyrochlore Lattice

Yuichi Otsuka·Tsuneya Yoshida·Koji Kudo·Seiji Yunoki·Yasuhiro Hatsugai
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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 $\mathbb{Z}_{4}$ 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.

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Yuichi Otsuka, Tsuneya Yoshida, Koji Kudo, Seiji Yunoki, Yasuhiro Hatsugai. 2021-10-25. Higher-Order Topological Mott Insulator on the Pyrochlore Lattice. https://doi.org/10.1038/s41598-021-99213-z

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