Influence of growth striations on para-ferroelectric phase transitions: Mechanism of the formation of periodic laminar domains in LiNbO3 and LiTaO3

Publisher Website
Google Scholar
Abstract
The concentration distributions of Y dopings in LiTaO3 across the growth striations in as‐grown crystals are obtained by means of x‐ray energy dispersive spectrum analysis in a scanning transmission electron microscope at room temperature. The results show that it is the concentration gradient of the dopings which determines the configurations of ferroelectric domains. The mechanism for the formation of the periodic laminar ferroelectric domains (PLFDs) is explained theoretically by considering the influence of the distributions of the dopings on the para‐ferroelectric phase transitions in LiTaO3 and LiNbO3 crystals. It is shown that the coupling between the order parameter and the conjugate external field, which results from the ambipolar diffusion or from the strain‐induced polarization mechanism associated with the dopings and their compensated point defects, is just the physical reason for the formation of such PLFDs in these two materials.