Low frequency admittance measurements of polycrystalline sodium niobate

Abstract

Complex admittance measurements for the polycrystalline sample of sodium niobate with nonstoichiometric composition has been carried out at very low frequencies with the help of direct phase-amplitude method. Results confirmes relaxation processes in the sample at these frequencies. Real part of admittance has been interpreted as the conductivity of the sample. Activation energy od the ac conductivity has been determined and related to the defect structure of the sample.