Neutron diffraction investigations of the electric field influence on the crystals of SrxBa1-xNb2O6 (x=0.70, 0.75)

The electric field influence on structure reconstructions was studied in a SrxBa1-xNb2O6 (x=0.70, 0.75) crystal on the time-of-flight neutron diffractometer. The measurements were conducted from room temperature up to 773 K in electric fields up to 4 kV/cm. At cooling a crystal under a field is observed the reduction of the diffraction peak integral intensity. When the field is applied to a crystal being in the state of thermal depolarization, the reflection intensities of the [001] type increase nonmonotonically due to the applied field. Field effects at room temperature clearly point to the existence inside a crystal of a ferroelectric domain structure with the opposite polarization direction in neighbouring domains. 13 refs.; 12 figs