New method for the visualization of domain and defect structure of ferroelectrics

Abstract

AbstractA new method for the visualization of domain and real structure of ferroelectric triglycine sulphate (TGS) crystals on the scale of optical microscopy by means of decoration with auramine is developed. Auramine deposits on crystal surfaces as discrete particles about 2 microns in size and as a continuous layer, thus allowing both the domains as a whole and the various electrically active elements of the domain and real TGS structure to be visualized with high resolution. Due to decoration with auramine, the domain structure of TGS detected with a very high contrast; elements of the geometrical relief‐cleavage steps exhibiting different electrical properties are also revealed. Furthermore, it has been observed for the first time that the positive domains have sharp electrical boundaries, while the negative domains have erased boundaries. It has also been established that between the domains of opposite signs regions exist characterized by a very low electrical activity. Decoration of annealed TGS crystals which were rapidly cooled from the temperature of 150°C, i.e. above the Curie point (49°C) down to room temperature resulted in detection of new electrically active directions on the surface of the negative domains; these directions are likely to occur in the paraelectric state. The new method cannot only be applied to the study of the TGS crystals but can also be useful in investigation of other ferroelectrics.