Peculiar ferroelectric and dielectric properties of quasiperiodic PbZr _0.4 Ti_0.6O₃ multilayers

Based on phase separation, quasiperiodic PbZr_0.4Ti _0.6O₃ (PZT) multilayers with alternating PZT and porous-PZT layers were fabricated by using a single precursor, and the ferroelectric and dielectric behaviours of the PZT multilayers were investigated. The PZT multilayers have an averaged remanent polarization of 42.3 μC cm^-2 and an average coercive field of 43 kV cm^-1. Two distinct dielectric relaxation phenomena were observed in the frequency range from 100 Hz to 1 MHz: the one at lower frequency is attributed to space charge polarization, while the one at higher frequency, with an activation energy of 0.49 eV, is expected to be associated with dipolar defect complexes related to oxygen vacancies.