By definition, magnetoelectric domains exhibit different tensor components of the magnetoelectric tensor when observed from the same coordinate system. Since direct detection of the magnetoelectric tensor components is difficult, it is advantageous to know in which other material tensor properties the magnetoelectric domains differ. If two magnetoelectric bulk structures (domain states) possess different spontaneous deformation, they can be simply observed in an optical microscope. Consequently, we limit our attention to non-ferroelastic magnetoelectric phases in which the domain states of different domains exhibit the same (zero) spontaneous deformation. The distinction between two non-ferroelastic magnetoelectric domains is determined by a point group generated by the point group of the domain state of the first domain and a space-time operation that relates this first domain state to the domain state of the second domain. The resulting point group is called the non-ferroelastic magnetoelectric twin law of the two domain states. Such an analysis is an extension of the recent work on tensor distinction of non-ferroelastic nonmagnetic domains.1-2 where it is shown that nonmagnetic twin laws are of the same mathematical structure as antisymmetric (dichromatic) point groups. We shall show that the corresponding magnetic twin laws are of the same mathematical structure as double antisymmetry point groups.3 We shall list all twin laws of two non-ferroelastic magnetoelectric domain states. For each of these twin laws we shall give the form of important property tensors that are different in the two magnetoelectric domain states under consideration.
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics