Ferroelectric domain structure of the BiFeO3 film grown on different substrates

Domain structure of BiFeO3 (BFO) films grown on different substrates, with a conductive La0.7Sr0.3MnO3 underlayer, has been experimentally studied. Two oppositely orientated polarizations, along the long body diagonal to the perovskite unit cell of BFO, are detected in the BFO films on the (0 0 1)-oriented NdGaO3. Electric pulses applied in the [0 0 1] direction produce a polarization switching, resulting in the domain structure characterized by the 109o domain walls. Contrary to the BFO films on NdGaO3, the BFO films on SrTiO3 (0 0 1) exhibit a much complex domain structure. Both 71o and 109o domain walls are possible with a uniform polarization component pointing to the bottom electrode. -- Research Highlights: → In this letter, the domain structure of BFO films grown on different substrates has been experimentally studied. → The domain structure of BFO/La0.7Sr0.3MnO3/NGO is rather simple, formed only by two oppositely directed polarizations. → Electric pulses can produce a polarization rotation, resulting in a transition of domain walls from 180o to 109o. → In contrast, the BFO films on STO (0 0 1) exhibit a much complex domain structure, and both 71o and 109o domain walls are possible, with a uniform polarization component pointing to the bottom electrode.