Ferroelectric control of antiferromagnetism via coordination swapping in A2Mo3O8 (A = Mn, Fe, Co)

Transition metal molybdenum oxides A2Mo3O8 (A = Mn, Fe, Co) are known to be polar magnets where A ions are located in either octahedrally or tetrahedrally coordinated sites. In this paper, we predict that their polarizations can be reversed via swapping of two coordinations for A ions, giving rise to robust vertical ferroelectricity. Such unique ferroelectricity via coordination swapping can be used to control the Neel vector in altermagnetic Fe2Mo3O8, while the large non-relativistic spin splittings can also be altered by ferroelectric switching in Luttinger compensated magnetic Mn2Mo3O8, both in the absence of net magnetization. However, their ultra-thin layers may possess nonzero net magnetizations that can be reversed upon ferroelectric switching. Such multiferroicity can go beyond conventional mechanisms, which may provide an efficient approach for data writing and reading in antiferromagnetic spintronics.