Ferroelectricity and ferromagnetism at room temperature rarely coexist in single compounds because the conditions conducive to each state are usually mutually exclusive. Multiferroics that display coupling between the magnetic and electric parameters, namely magnetoelectric coupling, at room temperature are even rarer. The scarcity of single-phase room-temperature multiferroic materials gave rise to the development of multiferroic composite materials in which the magnetoelectric effect originates from interface coupling. In the project ELMAGNANO (Electric field driven magnetization switching in multiferroic nanoislands), scientists achieved a breakthrough in multiferroic thin films. For the first time, they successfully demonstrated complete control of in-plane polarisation of bismuth ferrite (BFO) at the nanoscale using out-of-plane electric fields. This is an essential step to control magnetisation switching in such nanostructures. The study showed that polarisation in BFO nanostructures can be effectively toggled between any of the four polarisation variants pointing towards the bottom electrode; this feat has not been achieved in previous research. Each polar orientation can be selected through the raster scanning direction of the scanning probe microscopy probe. Project results show that it is possible to achieve deterministic ferroelectric polarisation switching in multiferroic nanostructures, which is important as it enables controlling the functionality of next-generation electronic devices based on magnetoelectric heterostructures.
Multiferroic, next-generation electronics, magnetoelectric, ELMAGNANO, deterministic switching