Bridging the immiscibility gap – making new compounds under pressure

• Applicant: Dr. Eteri Svanidze
• Subject Area: Solid State and Surface Chemistry, Material Synthesis ; Experimental Condensed Matter Physics
• Term: since 2024
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 553528746

Uranium-based quantum materials have recently entered a renaissance era – evidence of correlated topological states, spin-liquid behavior, hidden order phases, and spin-triplet superconductivity prove that these materials are exceptionally interesting. Because of their complex chemistry, many potentially fascinating uranium-based systems are currently entirely beyond the reach of conventional synthesis methods. The proposed project combines high-pressure high-temperature synthesis with micro-scale specimen isolation. This method will allow us not only to create previously inaccessible materials but also to definitively determine their crystal structure and physical properties. In particular, we propose to target several U-Ag, U-V, and U-Cr compounds with structures similar to known uranium-based superconductors. By employing advanced synthesis and characterization techniques, we will expand the family of uranium-based quantum systems and deepen our fundamental understanding of them. As part of our preliminary work, we have applied high-pressure high-temperature synthesis, coupled with subsequent isolation of micro-scale single-grain material, to the U-Ag binary system. Using this methodology, we have already identified several new U-Ag phases that exhibit superconductivity and ferromagnetism. By characterizing these exceptional materials under extreme conditions, we will gain further insights into synthesis optimization, helping to improve chemical composition and thus realize exotic chemistry and physics. To understand the underlying mechanisms of these intriguing phenomena, the nature of 5f-electrons (i.e., localized, itinerant, or both - the so-called “dual” nature) will be clarified by applying a combination of experimental tools readily available at the host institution. The ideas put forth in this proposal lie at the intersection of solid-state chemistry and condensed matter physics. By using advanced synthesis (simultaneous high-pressure high-temperature) and characterization (micro-scale isolation coupled with measurements under extreme conditions), we can access high-purity materials and study their novel crystallographic arrangements and exotic quantum states. The design and analysis of novel compounds discovered through this work will, therefore, enrich both chemistry and physics. Once this methodology is perfected, it will lead to significant advancements in the search for materials with exotic properties.

• DFG Programme: Research Grants