Bulk conduction and nonlinear behaviour in multiferroic YMnO3

Electrical conductivity of YMnO3 in O-2, air, and N-2 has been investigated by impedance spectroscopy. Within the investigated temperature range, three types of electrical conductivity were distinguished. Below 300 degrees C, the conductivity is dominated by p-type conductivity, while between 300 and 500 degrees C, the conductivity is in the so called saturation region. Above 500 degrees C, n-type conductivity occurred, probably due to the loss of oxygen. The air-processed YMnO3 is characterized by the presence of mixed Mn3+/Mn4+ and electrical heterogeneous structure, which are responsible for both, dielectric anomaly observed between 200 and 300 degrees C and nonlinear behavior under high electric field. (C) 2013 AIP Publishing LLC.