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 be also altered by ferroelectric switching in Luttinger compensated magnetic Mn2Mo3O8, both in the absence of net magnetization. However, their ultra-thin layers may possess net magnetizations that can be reversed upon ferroelectric switching. Our findings provide a new type of multiferroicity as well as a new avenue in control of antiferromagnetic spintronics.