2025/07/05 by Muzaffar, M. U., Bai, Kai-Zhi, Qin, Wei +5 · 1 citation
#FOS: Physical sciences #Materials Science (cond-mat.mtrl-sci) #Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
paper · doi:10.48550/arxiv.2507.03985
Integrating ferroelectricity, antiferromagnetism, and topological quantum transport within a single material is rare, but crucial for developing next-generation quantum devices. Here, we propose a multiferroic heterostructure consisting of an antiferromagnetic MnBi2Te4 bilayer and an Sb2Te3 film is able to harbor the half-quantized Hall (HQH) effect with a ferroelectrically switchable Hall conductivity of e2/2h. We first show that, in the energetically stable configuration, the antiferromagnetic MnBi2Te4 bilayer opens a gap in the top surface bands of Sb2Te3 through proximity effect, while its bottom surface bands remain gapless; consequently, HQH conductivity of e2/2h can be sustained clockwise or counterclockwise depending on antiferromagnetic configuration of the MnBi2Te4. Remarkably, when applying interlayer sliding within the MnBi2Te4 bilayer, its electric polarization direction associated with parity-time reversal symmetry breaking is reversed, accompanied by a reversal of the HQH conductivity. The proposed approach offers a powerful route to control topological quantum transport in antiferromagnetic materials by ferroelectricity.