Researchers from the Institute of Metal Research (IMR) of the Chinese Academy of Sciences (CAS) have directly observed polar Bloch points in strained ferroelectric films. Their work, published in Nature Communications, has expanded our understanding of topological ferroelectric domain structures and has implications for future integrated circuits and low-power electronic devices.
To make this discovery, the researchers considered the model of a tensile-strained ultrathin ferroelectric PbTiO3 film sandwiched by symmetric electrodes in phase-field simulations. They found that merons transform into Bloch points with the increase of electrode thickness.
Further experiments were conducted using aberration-corrected scanning transmission electron microscopic imaging on a trilayer SrRuO3/PbTiO3/SrRuO3 film grown on the SmScO3 substrate. The polarization configuration of polar Bloch points was observed and predicted to exist around each point using phase-field simulations.
The discovery of polar Bloch points expands our knowledge of topological ferroelectric domain structures and suggests new applications in future integrated circuits and low-power electronic devices. More information about this research can be found in the paper “Polar Bloch points in strained ferroelectric films” by Yu-Jia Wang et al, published in Nature Communications (2024). DOI: 10.1038/s41467-024-48216-1.
