Magnetoelectric coupling is crucial for spintronic applications of multiferroic materials; however, it is usually rather weak. Here, we propose that strong magnetoelectric coupling could be realized by electrical control of structural phase transition and spin-lattice interaction. Our first-principles calculations reveal two inequivalent stable multiferroic phases (denoted as $2H$ and $T^{″}$ phases) in a double transition metal dichalcogenide $\mathrm{NbV}{\mathrm{S}}_4$ monolayer. The $2H$ phase is ferromagnetic, while the $T^{″}$ phase is antiferromagnetic, and their in-plane ferroelectric polarizations are orthogonal. Therefore, a 90 ° rotation of the electric polarization is realizable by applying an electric field, which transforms the structural as well as the magnetic phases, leading to a strong magnetoelectric coupling. The emergence of such multistate multiferroicity with strong magnetoelectric coupling holds promising applications in high-density low-energy-dissipation memories.

Close

PrevNext

View figure in article

• Electric polarization
• Magnetoelectric effect
• Structural phase transition
• 2-dimensional systems
• Multiferroics
• Transition metal dichalcogenides
• First-principles calculations