The diffuseness of the ferroelectric phase transition in ${\mathrm{PbMg}}_{1/3}$ ${\mathrm{Nb}}_{2/3}$ ${\mathrm{O}}_3$ is proposed to be due to quenched random electric fields originating from charged compositional fluctuations. They are responsible for the extreme critical slowing down, the freezing into nanometric ferroelectric domains, and the slow relaxation of the polarization below ${\mathit{T}}_{\mathit{c}}$∼212 K. Barkhausen jumps during poling exclude glassiness, which was conjectured previously. At ${\mathit{T}}_{\mathit{c}}$ a ferroelectric anomaly of the dielectric permittivity appears, if the random fields are overcome by an external electric field.

The perpendicular exchange bias field, $H_{\mathrm{EB}}$, of the magnetoelectric heterostructure ${\mathrm{Cr}}_2{\mathrm{O}}_3(111)/(\mathrm{Co}/\mathrm{Pt}{)}_3$ changes sign after field cooling to below the Néel temperature of ${\mathrm{Cr}}_2{\mathrm{O}}_3$ in either parallel or antiparallel axial magnetic and electric freezing fields. The switching of $H_{\mathrm{EB}}$ is explained by magnetoelectrically induced antiferromagnetic single domains which extend to the interface, where the direction of their end spins controls the sign of $H_{\mathrm{EB}}$. Novel applications in magnetoelectronic devices seem possible.

The stability of electrically induced long-range ferroelectric order in a relaxor 0.94(Bi_1/2Na_1/2)TiO₃-0.06BaTiO₃ ceramic material has been investigated by temperature-dependent X-ray diffraction and electrical property measurements. The depolarization and ferroelectric-to-relaxor transition are identified as separate and discrete processes. It is observed that the induced ferroelectric domains first lose their ferroelectric/ferroelastic texture coincident with a peak signal in the thermally induced depolarization current. With further increase in temperature, the detextured ferroelectric domains are dissociated into nanoscale entities. This fragmentation marks the ferroelectric-to-relaxor transition. It is suggested that the ferroelectric-to-relaxor transition has features of a second order phase transition.