SUPPRESSION OF POLARIZATION SWITCHING IN TRIGLYCINE SULFATE CRYSTALS

Polarization switching in triglycine sulfate crystals with one of the polar surfaces covered by a thin dielectric film (1 mu m) has been fou nd to be highly diminished in a 50 Hz electric field. We assume that t he depolarization field caused by the him significantly moderates the process of the nucleation and (or) sideways motion of 180 degrees doma in walls. When crystals with both conductive electrodes were connected to the Sawyer-Tower circuit through the capacitor, which was equivale nt to the dielectric film, the polarization reversal did occur. We ass ume that in the case of the conductive electrode, a nonuniform distrib ution of the electrical charge at the electrode/ferroelectric interfac e and an injection current through the interface trigger off polarizat ion reversal. Analysis of the energetic state of the crystals has been performed. (C) 1996 American Institute of Physics.