MSE Seminar: Topological Superconductivity in Nearly Ferromagnetic UTe2
Speaker: Johnpierre Paglione, Director, Maryland Quantum Materials Center
Title: Topological Superconductivity in Nearly Ferromagnetic UTe2
Topological superconductivity has attracted great interest in condensed matter physics because of its potential applications in quantum computing. Spin-triplet superconductors are one promising class that can host the topological excitations of interest, but experimental realizations are few and far between. Here we report the discovery and properties of superconductivity in UTe2, a material closely related to known ferromagnetic superconductors such as UGe2, URhGe, and UCoGe, but lacking long-range magnetic order. Several experimentally measured properties feature telltale indications of an unconventional energy gap and a spin-triplet pairing state that is consistent with the presence of strong magnetic fluctuations due to an incipient quantum critical point. Furthermore, the superconductivity in UTe2 is remarkably robust to extremely high magnetic fields, showing re-entrant pairing up to at least 65 Tesla. I will review basic properties and our detailed investigations of the gap structure, relation to incipient magnetic order and Kondo coherence, as well as indications of an anomalous normal state fluid that suggest many surprises await for this exotic material.
Johnpierre Paglione has seeded a world-class effort on quantum materials research at UMD, leading the collaborations of several faculty that have brought Maryland to the forefront of research on superconductivity, topological materials and strongly correlated systems. Having contributed to several fields of experimental condensed matter research through both single-crystal synthesis and ultra-low temperature transport, thermodynamic and spectroscopic exploration of novel phenomena, Paglione’s research is a blend of materials exploration and elucidation of quantum phenomena. As Director of the Maryland Quantum Materials Center, with a membership of over 100 personnel, a state-of-the-art materials synthesis facility and an extensive measurement suite, Paglione commits QMC resources to hosting the annual Fundamentals of Quantum Materials Winter School, a successful hands-on training program and basis for this work. Paglione is the recipient of a National Science Foundation CAREER Award and an Early Career Award from the Department of Energy, is a Materials Synthesis Fellow in the EPiQS program of the Gordon and Betty Moore Foundation and a Fellow of the Quantum Materials Program of the Canadian Institute for Advanced Research. Dr. Paglione earned his PhD from the University of Toronto in Canada.