Intrinsic dielectric frequency dependent spectrum of a single domain tetragonal BaTiO₃ Available to Purchase

The intrinsic dielectric frequency dependent spectrum of single domain barium titanate (BaTiO₃) at room temperature is investigated by considering the vibration of phonons and the conductivity of the tetragonal system in a wide frequency range up to THz. The proposed model combines Debye type of dissipation, soft mode theory, and the influence of conductivity on the dielectric loss to obtain a more precise dielectric frequency spectrum. The calculated results were compared with experimental data on single domain nanocrystals of BaTiO₃, both free standing and suspended in a low dielectric medium. The comparisons provide insight into the mechanism for the dielectric behavior, which can be extended to apply to a range of composites that comprise single domain dielectrics embedded in continuous media. At the lower frequency range, conductivity plays a dominant role in the contribution to the dielectric loss along both a- and c-axes, while the phonon vibration controls the dielectric behavior of the system at higher frequency range. When the conductivity of the system increases, the dielectric loss increases below the MHz range, with such an effect diminishing when the frequency reaches the GHz regime.