Complete Selective Switching of Ferroelastic Domain Stripes in Multiferroic Thin Films by Tip Scanning

BiFeO3 is a rare single-phase multiferroic which shows coupled ferroelectricity, ferroelasticity and antiferromagnetism at room temperature. Many fantastic properties of BiFeO3 are regulated by its domain structure. While (001) rhombohedral BiFeO3 thin films can possibly develop up-to eight degenerate states of two-variant 71 degrees ferroelastic domain stripes, complete selective control of all possible switching paths between these states has not yet been achieved. Here, combining phase field simulations and scanning probe microscopy experiments, we demonstrated such a complete selective control. The tip bias and the built-in field were shown to affect the volume fraction of the 71 degrees, 109 degrees and 180 degrees switched domains in rhombohedral BiFeO3 thin films under single-point loading. Meanwhile, tip scanning further broke the symmetry of the nucleated domains, leading to different switched domain patterns. We then grew BiFeO3 thin films with a specific two-variant 71 degrees ferroelastic domain state and showed that such a state could be deterministically switched into the other seven two-variant domain states by collaborative controlling tip scanning and tip bias in scanning probe microscopy experiments. These results should deepen our current understanding on the domain switching kinetics in BiFeO3 thin films and indicate they are promising platforms for developing configurable electronic and spintronic devices. Via phase field simulations and scanning probe microscopy experiments, this work demonstrates a complete selective switching among eight degenerate states of two-variant 71 degrees ferroelastic domain stripes in BiFeO3 thin film by a collaborative control of tip scanning and tip bias. The results deepen the current understanding on the domain switching kinetics in BiFeO3 thin films and indicate they are promising platforms for developing configurable electronic and spintronic devices. image