Electric-field switching of the antiferromagnetic topological state in a multiferroic heterobilayer

Coupling nontrivial topological physics to ferroelectricity in two-dimensional lattice is highly desirable in both fundamental research and devices applications. Here, using first-principles calculations, we report that in a multiferroic heterobilayer consisting of a antiferromagnetic layer MnSe and a ferroelectric layer ${\mathrm{In}}_{2}{\mathrm{S}}_{3}$, the typical type-III band alignment can be realized. Upon introduction of spin-orbit coupling, a band gap is created, giving rise to a nontrivial antiferromagnetic topological phase. By reversing ferroelectric polarization, the nontrivial antiferromagnetic topology of $\mathrm{MnSe}/{\mathrm{In}}_{2}{\mathrm{S}}_{3}$ can be annihilated, yielding a wide-gap antiferromagnetic semiconductor with trivial physics. It thus proves to be a feasible approach to realize purely electric-field control of antiferromagnetic topological physics in this heterobilayer. The physical mechanism of such phenomenon is further unveiled to be related to the interlayer charge transfer between the two layers. These findings shed light on the design and control of antiferromagnetic topological physics in two dimensions.