Crystallographic Features of Ferroelectric Domain Structures in (Sr1-xBax)Bi2Ta2O9

The crystallographic features of the ferroelectric domain structures in (Sr1-xBax)Bi2Ta2O9 single crystals have been examined by transmission electron microscopy. The unique 90° domain structures were found in these single crystals. In SrBi2Ta2O9 with x = 0, particularly the majority domains with the ±[1 1 0]t polarization vectors in the tetragonal notation are divided by the minority ones with the vectors, which were observed as a curved-line contrast in dark field images.