In the present work, we study mixed compounds based on Ca0.28Ba0.72Nb2O6 (CBN28) calcium–barium niobate, and Sr0.61Ba0.39Nb2O6 (SBN61) strontium–barium niobate single crystals. It is shown that electron radiation in an electron microscope (with an accelerating voltage of 15 kV) during the scanning process induces the enhanced DC conductivity of samples along with a drastic rise in the dielectric constant. Furthermore, the dielectric constant as a function of the temperature changes its course, leading to a strong increase in dielectric loss at frequencies below 10 kHz.

In the present work, we aimed to find the correlation between the distribution of Ca, Ba and Sr over the volume and ferroelectric properties of CSBN materials. As a result, it is shown that in the CSBN25 which is characterized by relaxor properties there exists smaller excess oxygen compared with CSBN50 and CSBN75 crystals. CSBN25 also have more nonuniform distribution of elements, which occupy the same position (A1) in tetragonal tungsten bronze structure.

The pyroelectric response of systems composed of two layers having opposite polarization directions (bimorphs) is studied. It is found experimentally that both magnitude and shape of the pyroelectric response depend markedly on the ratio between the thicknesses of the layers. This result is confirmed by mathematical simulation based on the theory of thermal wave transmission through layered structures. The role of this effect on the performance of practical devices is discussed.

It is shown theoretically that in the method of conoscopy in the general case of arbitrary orientation of the optical axis (OA) and normal to the crystal surface, the isochromes should be described by the curves of the fourth order and higher. The existence of such type of isochromes is demonstrated experimentally. Examples of the computer calculation of the system of equations describing the isochrome shapes derived without commonly used approximations adopted in previous studies are presented.