Frequency dependence of the dielectric properties in MgO:LiNbO3crystals

MgO-doped congruent composition LiNbO3 crystals were grown by the Czochralski method. All MgO:LiNbO3 melts have a higher melting temperature than that of a pure one. Frequency dependence dielectric spectra were measured to study the relaxation and conduction mechanism of these crystals. Strong, low frequency dispersion indicated that the main conduction of MgO-doped LiNbO3 is the hopping charge carrier which may be caused by the defects or Mg-ions. Impedance spectra measurements show that this system does not satisfy a Debye but Jonscher's “Universal Law”