Electron microscopic studies of ferroelectric crystals

It is shown that a surprising variety of microstructural phenomena in ferroelectric materials are accessible by high-resolution electron microscopic techniques. Recent observations are reviewed concerning (i) domain wall widths and surface roughness in LiTaO3, KNbO3 and barium sodium niobate (BNN); (ii) microdomain textures and fluctuations at the cubic/tetragonal phase transition of BaTiO3; (iii) the commensurate superlattice structure of BNN and (iv) the hierarchy of chaotic states coexisting within the incommensurate superstructure phase of strontium barium niobate (SBN) at room temperature.