We theoretically propose a family of structurally stable monolayer halide perovskite A3B2C9 (A=Rb, Cs; B=Pd, Pt; C=Cl, Br) with easy magnetization planes. These materials are all half-metals with large spin gaps over 1~eV accompanying with a single spin Dirac point located at K point. When the spin-orbit coupling is switched on, we further show that Rb3Pt2Cl9, Cs3Pd2Cl9, and Cs3Pt2Cl9 monolayers can open up large band gaps from 63 to 103 meV to harbor quantum anomalous Hall effect with Chern numbers of C=±1, whenever the mirror symmetry is broken by the in-plane magnetization. The corresponding Berezinskii-Kosterlitz-Thouless transition temperatures are over 248~K. Our findings provide a potentially realizable platform to explore quantum anomalous Hall effect and spintronics at high temperatures.
@article{arxiv.2107.07381,
title = {Large-Gap Quantum Anomalous Hall Effect in Monolayer Halide Perovskite},
author = {Zeyu Li and Yulei Han and Zhenhua Qiao},
journal= {arXiv preprint arXiv:2107.07381},
year = {2021}
}