EurekAlert February 9, 2022
An international team of researchers (UK, Ireland, USA – Argonne National Laboratory) created a thin film of the ferroelectric lead titanate sandwiched between layers of the ferromagnet strontium ruthenate, each about 4 nanometres thick. The structure of the combined layers revealed that the domains in the lead titanate were a complex topological structure of lines of vortexes, spinning alternately in different directions. Almost identical behaviour has also been seen in ferromagnets where it is known to be generated by the Dzyaloshinskii–Moriya interaction (DMi). According to the researchers the difference between ferromagnetism and ferroelectricity becomes less and less important. It might be that they will merge at some point in one unique material. This could be artificial and combine very small ferromagnets and ferroelectrics to take advantage of these topological features. DMi plays a pivotal role in stabilizing topological magnetic structures, such as skyrmions, and it might be crucial for potential new electronic technologies exploiting their electrical analogues…read more. TECHNICAL ARTICLEÂ
…3D model of the polarisation pattern in the ferroelectric PbTiO3 representing the cycloidal modulation of the vortex core. CREDIT: University of Warwick