Van der Waals (vdW) heterostructures formed by two-dimensional magnets and semiconductors have provided a fertile ground for fundamental science and for spintronics. We present first-principles calculations finding a proximity exchange splitting of 14 meV equivalent to an effective Zeeman field of 120 T in the vdW magnet-semiconductor heterostructure MoS2/CrBr3, leading to a 2D spin-polarized half-metal with carrier densities ranging up to 1013 cm−2. We consequently explore the effect of large exchange coupling on the electronic bandstructure when the magnetic layer hosts chiral spin textures such as skyrmions. A flat Chern band is found at a "magic" value of magnetization m∼0.2 for Schr\"odinger electrons, and it generally occurs for Dirac electrons. The magnetic proximity induced anomalous Hall effect enables transport-based detection of chiral spin textures, and flat Chern bands provides an avenue for engineering various strongly correlated states.
@article{arxiv.2111.01805,
title = {Giant proximity exchange and flat Chern band in 2D magnet-semiconductor heterostructures},
author = {Nisarga Paul and Yang Zhang and Liang Fu},
journal= {arXiv preprint arXiv:2111.01805},
year = {2023}
}
Comments
5+4 pages, 7 figures; v2 accepted to Science Advances