Ultrawide range dielectric spectroscopy of BaTiO3-based perovskite dielectrics

Ultrawide range dielectric spectra from the kilohertz to terahertz range of BaTiO3 (BT), Ba (Zr0.25Ti0.75)O-3 (BZT), (Ba0.6Sr0.4)TiO3 (BST), and SrTiO3 ceramics were presented by analyzing dielectric permittivity and IR reflectivity data. It was found that the permittivity of the ST was determined only by the ionic polarization while that of the BT was determined by the ionic polarization as well as the dipole polarization due to the domain contribution. The high permittivity of the BZT ceramics was attributed to the dipole polarization of polar nanoregions in the relaxors. The dipole and ionic polarizations overlapped in the BST. (C) 2007 American Institute of Physics.