Electric-field effects on the diffuse scattering in PbZn1/3Nb2/3O3 doped with 8% PbTiO3 -: art. no. 014110

We report measurements of the neutron diffuse scattering from a single crystal of the relaxor ferroelectric PbZn1/3Nb2/3O3 doped with 8% PbTiO3 (PZN-8%PT) for temperatures 100 Kless than or equal toTless than or equal to530 K and electric fields 0 kV/cmless than or equal toEless than or equal to10 kV/cm. The field-cooled diffuse scattering measured transverse to the (003) Bragg peak is strongly suppressed in the tetragonal phase at 400 K for E=2 kV/cm applied along the [001] direction. However, no change is observed in the diffuse scattering measured transverse to (300), even for field strengths up to 10 kV/cm. Thus the application of an external electric field in the tetragonal (ferroelectric) phase of PZN-8%PT does not produce a uniformly polarized state. This unusal behavior can be understood within the context of the model of Hirota of phase-shifted polar nanoregions in relaxors, since an electric field applied along [001] below T-c would reduce the shifts of the nanoregions along [001] while preserving those along the orthogonal [100] direction.