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arXiv · 2505.19204

A many-body marker for three-dimensional topological insulators with inversion symmetry

Federico Becca·Alberto Parola
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Abstract

We extend the previously defined many-body marker for two-dimensional $\mathbb{Z}_2$ topological insulators [I. Gilardoni {\it et al.}, Phys. Rev. B {\bf 106}, L161106 (2022)] to distinguish trivial, weak-, and strong-topological insulators in three dimensions, in presence of the inversion symmetry. The marker is written in term of ground-state expectation values of position operators and can be employed to detect topological phases of interacting systems beyond mean-field approximations, e.g., within quantum Monte Carlo techniques. Here, we show that the correct results of the non-interacting limit are reproduced by the many-body marker.

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Federico Becca, Alberto Parola. 2025-05-25. A many-body marker for three-dimensional topological insulators with inversion symmetry. https://arxiv.org/abs/2505.19204

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