Poling-field modulation of electric polarization in multiferroic phases of MnWO4

Type-II multiferroics host spin-driven ferroelectricity with strong magnetoelectric coupling. Here, we report the first successful growth of high-quality MnWO4 single crystals using chemical vapor transport, unlike previous flux or optical floating-zone methods. We systematically characterized their magnetic and ferroelectric properties. In the incommensurate helical AF2 phase, which lies between approximately 8 and 13 K, we observed the expected spin-driven electric polarization. This polarization can be effectively tuned by an external poling electric field Ep, demonstrating controllable domain wall depinning. To interpret these results, we performed phenomenological Landau–Ginzburg simulations incorporating a distribution of pinning potentials. Our findings provide a clear experimental basis for manipulating macroscopic magnetoelectric responses in type-II multiferroics.