Altermagnets provide promising platforms for unconventional magnetism, whose controllability would enable a whole new generation of spintronic devices. While a variety of bulk altermagnets have been discovered, altermagnetism in two-dimensional van der Waals materials has remained elusive. Here we demonstrate that the strained honeycomb monolayer VCl3 is an orbital-order-driven ferroelectric altermagnet, exhibiting a significant and switchable spin-splitting. By using low-energy Hamiltonian and first-principles methods in combination with symmetry analysis, we reveal a unique anti-ferro-orbital-antiferromagnetic phase characterized by a 2D nematic d-wave altermagnetic spin splitting, tightly coupled with an orbital-ordered induced ferroelectric polarization. Finally, through symmetry mode analysis, we investigate how structural distortions favor the intricate interplay between orbital, altermagnetic, and ferroelectric degrees of freedom. Our study identifies VCl3 as a prototypical 2D orbital-order-driven multiferroic altermagnet on the honeycomb lattice, establishing a van der Waals monolayer featuring altermagnetic ferroelectricity.
@article{arxiv.2503.19987,
title = {Multiferroic nematic d-wave altermagnetism driven by orbital-order on the honeycomb lattice},
author = {Luigi Camerano and Adolfo O. Fumega and Jose L. Lado and Alessandro Stroppa and Gianni Profeta},
journal= {arXiv preprint arXiv:2503.19987},
year = {2025}
}