The crucial role of Mn spiral spin order in stabilizing the Dy–Mn exchange striction in multiferroic DyMnO3†
*a
and
Abstract
DyMnO3 hosts the less addressed duality of multiferroicity, owing to the Dy–Mn exchange striction and inverse Dzyaloshinskii–Moriya interaction between Mn spin pairs. Although the duality in DyMnO3 has been discussed earlier, there remains a question whether the Mn magnetic sublattice is necessarily multiferroic for generating the Dy–Mn exchange striction. In this work, we investigate the multiferroicity of Dy(Mn1−xFex)O3 (0 ≤ x ≤ 0.1) through detailed magnetic and ferroelectric characterization. It is found that Fe-doping continuously suppresses the independent Dy spin order but instead promotes the Dy–Mn(Fe) coupling. This coupling benefits the Dy–Mn(Fe) exchange striction which remarkably enhances the ferroelectric polarization at a low doping level (x ≤ 0.015), beyond which the Mn spiral spin order breaks down leading to collapse of the macroscopic polarization at x ≥ 0.05. This work discloses the crucial role of Mn spiral spin order in stabilizing the Dy–Mn exchange striction and thus highlights the duality of multiferroicity in DyMnO3.
Please wait while we load your content...
