Symmetry theory of the flexomagnetoelectric effect in the magnetic domain walls

A local flexomagnetoelectric (A.P. Pyatakov, A.K. Zvezdin, 2009) effect in the magnetic domain walls (DWs) of the cubic hexoctahedral crystal has been investigated on the basis of a symmetry analysis. The strong connection between magnetic symmetry of the DW and the type of the distribution of the electric polarization was shown. Results were systemized in the scope of the DW chirality. It was shown, that new type of the local flexomagnetoelectric coupling corresponds to the presence of the coupled electric charge in the DW. It was found that all time-noninvariant chiral DWs have identical type of spatial distribution of the magnetization and polarization. There are coincidence between the symmetry predictions and results obtaining from the known term of the flexomagnetoelectric coupling for transverse polarization components.

Research Highlights
► Symmetry allows flexomagnetoelectric effect in any magnetic domain wall (DW).
► Known type of flexomagnetoelectric effect induces transverse components.
► Undiscovered type of flexomagnetoelectric effect induces the coupled charge.
► Results were systemized in the scope of the DW chirality.
► Both time-invariant and time-noninvariant chirality have been considered.