Magnetic Phase Boundary Mapping for the Discovery of Emergent Properties in Intermetallic Magnets

NON-TECHNICAL SUMMARY Itinerant (metallic) magnets are a unique class of magnetic materials used in societally important information and clean-energy technologies, including spin valves, novel electronic devices, electric vehicles, wind turbines, and magnetic refrigerators. Early studies offered understanding of magnetism in simple metals – iron, cobalt, and nickel. The present state of knowledge and advanced experimental and theoretical tools available to materials scientists afford insight into magnetic behavior of more complex intermetallic systems. Moreover, these tools allow not only investigation but also prediction of desired electronic and magnetic properties. With this project, supported by the Solid State and Materials Chemistry Program in NSF’s Division of Materials Research, Professor Michael Shatruk at the Florida State University will leverage the advanced theoretical methods and extensive experimental studies to fine-tune materials’ crystal and electronic structures in order to find states in which magnetic moments attain exotic configurations, such as helices, spirals, and vortices. The outcome of these studies will be rational design of materials with novel magnetic properties, paving the way to new properties that can be implemented in novel devices. The diversity of theoretical and experimental tools employed in this project will provide unique research training for graduate and undergraduate students, who will become proficient in solid state chemistry, materials synthesis and characterization, and quantum-chemical calculations. TECHNICAL SUMMARY Magnets with collinear arrangement of magnetic moments, such as canonical ferro-, ferri-, and antiferromagnets, have long been an area of active studies and innovations in solid state chemistry and condensed matter physics. Modern solid-state sciences provide powerful tools to explore the design of materials with competing magnetic interactions that can result in non-collinear magnetic structures, such as helical, spiral, or skyrmionics spin textures. This project aims to develop rational pathways to such materials by implementing a concept of magnetic phase boundary mapping. The phase space between two collinear magnetic structures (e.g., ferro- and antiferromagnetic) will be probed by a range of structural, magnetic, and spectroscopic techniques, as well as by electronic structure calculations, to uncover the region of non-collinear spin textures that are highly sensitive both to chemical substitutions and to applied magnetic fields or pressure. The project will make active use of advanced large-scale research facilities at national labs for determination of magnetic structures and detailed structure-property correlations. The proposed research activities will provide versatile training to graduate and undergraduate students in materials synthesis, investigation of structural and magnetic properties, the use of neutron scattering methods, and studies of the electronic band structure. The students will be involved in active collaborations with researchers at neutron and X-ray scattering facilities. The PI and his research group will contribute to broadening participation by involving students from underrepresented groups through a transitional master-to-PhD bridge program in chemistry, organization of undergraduate summer schools in magnetism and magnetic materials, and implementation of the unique MINDLab research experiences aimed at high-school students. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.