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, focusing on the substrate engineering and aiming to understand how different substrates modify the electronic structure and topological phases of V2O3 monolayers. 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 introduce additional magnetic exchange fields and interfacial charge transfer, which significantly perturb the electronic structure of V2O3 and shift the Fermi level, thereby destroying the QAH state. 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.