Speaker: Filip Ronning, Los Alamos National Lab

Host: Chandan Setty

Title: The emergent heavy fermion multiverse

Abstract: Materials are the foundation of the world around us. As new materials open opportunities for developing new technologies, they also extend a materials multiverse - providing us with opportunities to explore new fundamental physics. Every material possesses a unique low-energy Hamiltonian, and as such, is its own “universe”. Each material’s universe contains excitations, which at times can resemble familiar particles such as electrons, but at other times can show fractionalized excitations with dramatically different quantum numbers. f-electron-based heavy fermion materials, where the effective mass of the low-energy charge excitations can reach 1,000 times that of a bare electron, are prototypical strongly correlated materials with exotic ground states including magnetic, multipolar, and/or nematic order, unconventional superconductivity, non-trivial topology, and other new states that continue to surprise us. In this talk, I will review a few examples of the novel particles that emerge within the heavy fermion multiverse. 

Bio: Filip Ronning received a B.A. in Physics from Cornell University and a Ph.D. from Stanford University for angle-resolved photoemission work on strongly correlated oxides. Following two years at the University of Toronto, he joined Los Alamos National Lab in 2003. His scientific interests include (but are not limited to) topological matter, quantum spin systems, heavy-fermion physics, unconventional superconductivity, quantum criticality, low-dimensional physics, spin-orbit coupled systems, dark matter, and new states of matter. A LANL distinguished mentor, in 2015 he was elected a fellow of the American Physical Society, and in 2023 he became a fellow of Los Alamos National Lab. In his free time, he enjoys spending time with his family and playing any sport his body still permits.