Symmetry considerations in commensurate and incommensurate multiferroic materials

On the symmetry and the signature of atomic mechanisms in multiferroics: the example of Ba₂CoGe₂O₇

The peculiar magnetoelectric properties of Ba₂CoGe₂O₇ are explained by making use only of symmetry arguments and symmetry-based phenomenology. This remarkable example shows the general need for a systematic application of magnetic symmetry in the study of multiferroics.