Magnetoelectric multiferroic materials exhibit both magnetic and electrical spontaneous polarisations and could be used in a range of devices for the manipulation and storage of digital information. However, the properties that are required for ferroelectric and ferromagnetic behaviour are contradictory, making materials that exhibit both very difficult to design.
Image: The refined magnetic structure of MnSrTa2O7. Pink and purple spheres represent Mn cations, green and orange arrows indicate the direction of the ordered magnetic moments.
One method, explored in this study, is to introduce magnetic cations into a ferroelectric structure, which then leads to magnetoelectric coupling. In this example, the researchers performed low temperature cation-exchange reactions on Li2SrTa2O7 to form MnSrTa2O7. By using neutron diffraction, they were able to investigate the magnetic ground state formed, finding that they had successfully formed a coupled magnetoelectric material. This technique could, in the future, be applied to other host phases, widening the pool of candidates of materials with this unique and sought-after property.
Related publication: Directed synthesis of a hybrid improper magnetoelectric multiferroic material, Nature Communications, 12, 4945 (2021) DOI: 10.1038/s41467-021-25098-1