Neutron Scattering from the Ferroelectric Fluctuations and Domain Walls of Lead Germanate

Abstract

Neutron scattering from the uniaxial ferroelectric ${\mathrm{Pb}}_5$ ${\mathrm{Ge}}_3$ ${\mathrm{O}}_{11}$ shows a quasielastic component in addition to the soft ferroelectric mode. At low temperatures, this scattering increases but can be suppressed by an applied electric field and probably arises from scattering by static domain walls. This scattering also has a maximum near $T_c$ which is largely field independent and which we suggest may arise from scattering by the walls of moving domains or clusters.