Dielectric Relaxation in Disordered Polar Dielectrics

A review of the current understanding of the effect of crystal lattice defects on the low-frequency dielectric relaxation properties in single crystals and polycrystalline polar dielectrics is given. Special attention is paid to different long-term phenomena, found in dielectric experiments, such as a low frequency relaxation polarization, a very slow relaxation of metastable states, a dielectric dispersion with a broad spectrum of distribution of relaxation times, a nonergodic behavior of the remanent polarization, etc. Mechanisms for dielectric loss and permittivity taking into account kinetics of defects rearrangement and their interactions in disordered inhomogeneous polar dielectrics are assessed.

Keywords:

• Polar Dielectrics
• Disorder
• Dielectric Relaxation
• Metastable State
• Dipolar Glass
• Relaxor