Magneto-optical effects (MOE), interfacing the fundamental interplay between magnetism and light, have served as a powerful probe for magnetic order, band topology, and valley index. Here, based on multiferroic and topological bilayer antiferromagnets (AFMs), we propose a layer control of MOE (L-MOE), which is created and annihilated by layer-stacking or an electric field effect. The key character of L-MOE is the sign-reversible response controlled by ferroelectric polarization, the Neel vector, or the electric field direction. Moreover, the sign-reversible L-MOE can be quantized in topologically insulating AFMs. We reveal that the switchable L-MOE originates from the combined contributions of spin-conserving and spin-flip interband transitions in spin-valley splitting AFMs, a phenomenon not observed in conventional AFMs. Our findings bridge the ancient MOE to the emergent realms of layertronics, valleytronics, and multiferroics and may hold immense potential in these fields.
@article{arxiv.2403.16701,
title = {Layer Control of Magneto-Optical Effects and Their Quantization in Spin-Valley Splitting Antiferromagnets},
author = {Jiaqi Feng and Xiaodong Zhou and Meiling Xu and Jingming Shi and Yinwei Li},
journal= {arXiv preprint arXiv:2403.16701},
year = {2024}
}