Dr. Marta Gibert, from TU Wien, presented her research on engineering magnetism in double-perovskite oxide heterostructures, a promising field for multiferroic devices. The lecture, held on Monday, October 26, 2026, at 12:00 PM, took place at the Sala d'Actes MATGAS of ICMAB - CSIC and was also streamed online.
Atomically engineered transition-metal-oxide heterostructures provide a versatile platform for probing and tailoring magnetic properties at the ultrathin limit and across interfaces. Materials that are both ferromagnetic and insulating are rare, yet they are key to spin-based and multifunctional devices. The RE₂NiMnO₆ (RE = rare earth) double-perovskite family is one of the few combining these two properties. La₂NiMnO₆ exhibits a Curie temperature (Tc) of 280 K, while Tc decreases linearly with decreasing RE radius.
In epitaxial RE₂NiMnO₆ thin films, ferromagnetism survives down to a few atomic layers, and it has been shown to be retained in free-standing membranes. To engineer the magnetic phase diagram and probe interfacial coupling, atomically controlled superlattices (artificial stacks of alternating layers) of La₂NiMnO₆ and RE₂NiMnO₆ (RE = Nd, Sm), compounds with distinct Curie temperatures, were fabricated. Large-period superlattices display two separate magnetic transitions, while reducing the layer thickness yields a single transition, indicating that short-period heterostructures behave as a single material.
Electron microscopy and first-principles calculations reveal unequal antipolar cation displacements in these superlattices, consistent with a net electric polarization and suggesting hybrid improper ferroelectricity. Combined with robust ferromagnetism, these results highlight double-perovskite heterostructures as a promising platform for multiferroic devices.
“"Our results highlight double-perovskite heterostructures as a promising platform for multiferroic devices."
Marta Gibert studied Physics at the Autonomous University of Barcelona and obtained her PhD in 2009 at the Institute of Materials Science of Barcelona (ICMAB-CSIC). She has conducted research internships in Germany, the UK, and the USA, receiving the Extraordinary PhD Award in Physics for her research on self-assembled oxide nanostructures. Since September 2021, she has been a full professor at the Institute of Solid State Physics at TU Wien (Vienna, Austria). In 2016, she was awarded the IBM Prize in Condensed Matter Physics by the Swiss Physical Society.
