Ferroelectric control of magnetic skyrmions in two-dimensional van der Waals heterostructures

Abstract: Magnetic skyrmions are chiral nanoscale spin textures which are usually induced by Dzyaloshinskii-Moriya interaction (DMI). Recently, magnetic skyrmions have been observed in two-dimensional (2D) van der Waals (vdW) ferromagnetic materials, such as Fe${3}$GeTe${2}$. The electric control of skyrmions is important for their potential application in low-power memory technologies. Here, we predict that DMI and magnetic skyrmions in a Fe${3}$GeTe${2}$ monolayer can be controlled by ferroelectric polarization of an adjacent 2D vdW ferroelectric In${2}$Se${3}$. Based on density functional theory and atomistic spin-dynamics modeling, we find that the interfacial symmetry breaking produces a sizable DMI in a Fe${3}$GeTe${2}$/In${2}$Se${3}$ vdW heterostructure. We show that the magnitude of DMI can be controlled by ferroe-lectric polarization reversal, leading to creation and annihilation of skyrmions. Furthermore, we find that the sign of DMI in a In${2}$Se${3}$/Fe${3}$GeTe${2}$/In${2}$Se${3}$ heterostructure changes with ferroelectric switching reversing the skyrmion chirality. The predicted electrically controlled skyrmion formation may be interesting for spintronic applications.