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arXiv · 2505.13795

Substrate Effect on Electronic Band Structure and Topological Property in Monolayer V2O3 Magnetic Topological Insulator

Abstract

Monolayer V2O3, a two-dimensional magnetic topological insulator with intrinsic ferromagnetic order and a nontrivial band gap, offers a promising platform for realizing quantum anomalous Hall (QAH) states. Using first-principles density functional theory calculations, we systematically investigate the impact of substrate selection on its electronic and topological properties. By modeling heterostructures with van der Waals (vdW) substrates, we demonstrate that non-magnetic substrates such as h-BN preserve the QAH phase with a Chern number C = 1, maintaining gapless chiral edge states. In contrast, ferromagnetic substrates induce extra electrons, destroying the topological order by shifting the Fermi level. These findings establish substrate engineering as a pivotal strategy for experimental realization of dissipationless edge transport in V2O3-based vdW heterostructures, advancing their potential applications as low-power topological electronics.

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Zheng Wang, Jingshen Yan, Shu-Shen Lyu, Kaixuan Chen. 2025-05-30. Substrate Effect on Electronic Band Structure and Topological Property in Monolayer V2O3 Magnetic Topological Insulator. https://doi.org/10.1039/d5cp02043c

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