Using the density functional theory calculations, we predict that several monolayer chromium-based materials exhibit a triple-Q tetrahedral magnetic insulating ground state. By studying the effect of biaxial strain on monolayer CrSi2P4 under various on-site Coulomb interactions, we reveal that this magnetic insulating state, sandwiched between the itinerant 120∘ coplanar noncollinear antiferromagnetic and ferromagnetic states, originates from the competition between antiferromagnetic exchange and double exchange interactions of Cr 3d electrons which can also be applied to account for the ground states in other chromium-based materials. Remarkably, anomalous valley Hall effect with giant valley splitting is discovered in the magnetic states of these inversion-asymmetric systems without requiring spin-orbit coupling or net magnetization. Our findings open a new avenue towards exploring monolayer materials for valleytronics.
@article{arxiv.2505.02559,
title = {Anomalous valley Hall effect in monolayer chromium-based triple-Q magnets},
author = {Xiu-Cai Jiang and Li-Ya Qiao and Yu-Zhong Zhang},
journal= {arXiv preprint arXiv:2505.02559},
year = {2025}
}