Dielectric relaxation and electrical conductivity of random oriented BiFeO3 thin films.

Complex impedance and electric modulus spectroscopies were used to investigate the dielectric relaxation and conductivity of random oriented BiFeO₃ thin films. Thermally activated charge transport models yielded activation energies of eV, which is consistent with an electrical conduction dominated by oxygen vacancies. The non-Debye behavior of impedance and electric modulus relaxations were modeled by Cole-Cole functions. Results suggest a coexistence of components from both long-range and localized relaxation in the studied BiFeO₃ films dominated by grain boundaries. The dielectric relaxation induced by electric field does not follow the Arrhenius formalism. [ABSTRACT FROM AUTHOR]