Abstract
The temperature dependences of the pyroelectric coefficient of lithium niobate single crystals grown from a congruent melt have been investigated in the range of 4.2–300 K. No anomalies were found at low temperatures, and the experimental dependence is described well by the Debye-Einstein model, with TD = 357 K and two pyroactive frequencies of 692 and 869 cm−1. Specific features of lithium niobate have been analyzed. Two sublattices, formed by two pairs of mesotetrahedra with (according to the symmetry conditions) dipole and octupole moments, were selected in the structure. Their contributions to the total polarization differ by an order of magnitude. Vacuum annealing of the samples leads to the occurrence of anomalies only at temperatures over 280 K; these anomalities are interpreted as a manifestation of superionic conductivity.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.