Electrically Switchable Topological Magnetic Phase Transition in 2D Multiferroics.

Abstract

Phase transitions between different topological spin structures represent a captivating class of phenomena that have attracted tremendous interest due to their rich physics and promising applications. However, existing methodologies for their realization and manipulation remain confined to a conventional vertical magnetic-field reversal mechanism. By combining first-principles calculations with atomistic spin simulations, we report a novel electrically driven topological magnetic phase transition in van der Waals multiferroic heterobilayer NiSeCl/Sc₂CO₂. Notably, electric-field-induced ferroelectric switching in the Sc₂CO₂ layer enables alternating emergence of skyrmion and bimeron states in an adjacent NiSeCl layer, realizing electric-field control over the topological magnetic phase transition between these two distinct quasiparticle states. Our analysis reveals that such behavior originates from the delicate interplay between in-plane magnetic anisotropy and the competing Heisenberg exchange versus Dzyaloshinskii-Moriya interaction, which can be effectively modulated through ferroelectricity. These results advance fundamental research in topological magnetism and enable voltage-programmable topological spintronics.