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DOE OSTI · 3017370

Correlation-driven topological band inversion in VSe 2

Ng, Yi Sheng [Xiamen Univ. Malaysia, Sepeng (Malaysia)]·Yilmaz, Turgut [Xiamen Univ. Malaysia, Sepeng (Malaysia); Univ. of Connecticut, Storrs, CT (United States)] (ORCID:0000000267358088)·Rajapitamahuni, Anil [Brookhaven National Laboratory (BNL), Upton, NY (United States). National Synchrotron Light Source II (NSLS-II)] (ORCID:0000000330924258)·Kundu, Asish [Brookhaven National Laboratory (BNL), Upton, NY (United States). National Synchrotron Light Source II (NSLS-II)]·Vescovo, Elio [Brookhaven National Laboratory (BNL), Upton, NY (United States). National Synchrotron Light Source II (NSLS-II)] (ORCID:0000000303503861)·Sinkovic, Boris [Univ. of Connecticut, Storrs, CT (United States)] (ORCID:0000000227419114)·Wang, Hui-Qiong [Xiamen Univ. Malaysia, Sepeng (Malaysia)]·Zheng, Jin-Cheng [Xiamen Univ. Malaysia, Sepeng (Malaysia)] (ORCID:0000000262923236)
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Abstract

Recent spectroscopic studies have uncovered topological surface states and band inversion in 1⁢T−VSe 2 , positioning this material at the intersection of correlated electron physics and nontrivial band topology. While previous interpretations attribute these features to surface strain, the microscopic origin of the topological band structure remains unresolved. Here, we present an alternative explanation based on electronic correlations, showing that a negative effective Hubbard interaction (𝑈 eff < 0) applied to the Se 4p orbitals can reproduce the experimentally observed band inversion at both the Γ and 𝑀 points. Using density functional theory (DFT) calculations with orbital-selective interactions, we demonstrate that this approach naturally gives rise to topological surface states without invoking structural distortions. In conclusion, our results highlight the crucial role of ligand orbital correlations in shaping band topology and provide a novel framework for understanding and engineering topological phases in chalcogenide-based quantum materials.

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36 MATERIALS SCIENCEElectronic structureSpin-orbit couplingSurface statesTopological phases of matter

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Ng, Yi Sheng [Xiamen Univ. Malaysia, Sepeng (Malaysia)], Yilmaz, Turgut [Xiamen Univ. Malaysia, Sepeng (Malaysia); Univ. of Connecticut, Storrs, CT (United States)] (ORCID:0000000267358088), Rajapitamahuni, Anil [Brookhaven National Laboratory (BNL), Upton, NY (United States). National Synchrotron Light Source II (NSLS-II)] (ORCID:0000000330924258), Kundu, Asish [Brookhaven National Laboratory (BNL), Upton, NY (United States). National Synchrotron Light Source II (NSLS-II)], Vescovo, Elio [Brookhaven National Laboratory (BNL), Upton, NY (United States). National Synchrotron Light Source II (NSLS-II)] (ORCID:0000000303503861), Sinkovic, Boris [Univ. of Connecticut, Storrs, CT (United States)] (ORCID:0000000227419114), Wang, Hui-Qiong [Xiamen Univ. Malaysia, Sepeng (Malaysia)], Zheng, Jin-Cheng [Xiamen Univ. Malaysia, Sepeng (Malaysia)] (ORCID:0000000262923236). 2025-12-01. Correlation-driven topological band inversion in VSe 2. https://doi.org/10.1103/38pr-lkrl

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36 MATERIALS SCIENCE↗