Investigation of large dielectric permittivity and relaxation behavior of DyMnO3 single crystal

We have investigated the frequency-dependent dielectric properties of DyMnO 3 single crystal in the temperature region from 100 K to 320 K. The material shows a large dielectric permittivity in the low-frequency range around room temperature. The dielectric permittivity exhibits a strong temperature dependence at all frequency and two anomalies which can be associated with the Debye-type relaxation with activation energies of 0.66 eV and 0.23 eV in the higher (around 300 K) and lower (around 150 K) temperature regions, respectively. The high value of activation energy around room temperature suggests that the relaxation is associated to the charge carriers hopping resulting from the second ionization of oxygen vacancies . However, the impedance analysis suggests that the low-temperature relaxation is due to the Maxwell–Wagner type effects originating from the dipoles at the surface. • This article presents the detailed analysis of the dielectric relaxation behavior of DyMnO3 single crystal in the temperature range 100 K to 320 K. • We found two dielectric anomalies in this temperature region. • The activation energies are found to be of 0.66 and 0.23 eV in the higher and lower temperature regions, respectively. • Our result on single crystalline DyMnO3 indicates that relaxation around 150K is due to the universal Maxwell-Wagner type effects. • The high temperature relaxation anomaly with activation energy 0.66 eV can be ascribe to the hopping of charge carriers resulting from second ionization of oxygen vacancies.