Colloquium: Emilia Morosan, Rice University
Novel physics discoveries heavily rely on the design and synthesis of new materials, which, in turn, depends a lot on the growth method. I will use the backdrop of my group’s discoveries of several Kondo systems, to emphasize the importance of the interplay between chemistry, materials science and physics in unveiling new materials’ properties. In particular, I will focus on YbT3M7 where the transition metal T is either Rh or Ir, and the metal M is Si or Ge. These are rhombohedral compounds, chemically and structurally very similar, with some similar physical properties and substantive differences. They all show evidence for strong electronic correlations and Kondo physics; one orders ferromagnetically (YbIr3Ge7) while the other two have antiferromagnetic ground states. Most remarkable, YbIr3Si7 shows long range antiferromagnetic order and non-Fermi liquid behavior even within the ordered state, while the electrical resistivity indicates bulk insulating behavior with ARPES and DFT calculations pointing to a conductive surface. We reconcile the observed Kondo physics, long range magnetic order and the insulating-to-metal crossover from bulk to surface with a proposal of Kondo exhaustion and evience for a Yb valence transition from magnetic (3+ in the bulk) to non-magnetic (2+ on the surface).
About Emilia Morosan:
Emilia Morosan is a Professor of Physics and Astronomy, Chemistry and Materials Science and Nanoengineering at Rice University in Houston TX. She joined Rice in 2007, following doctoral work in Physics at Iowa State University and Ames Lab, and a postdoctoral position in Chemistry at Princeton University. She received several early career awards, including the Presidential Early Career Award for Scientist and Engineers (PECASE) and the NSF CAREER, and was recently selected as a EPiQS Investigator by the Gordon and Betty Moore Foundation. When not "cooking" in the lab, Emilia enjoys baking, gardening, kayaking, rock climbing, and most mornings you can join her for a bike ride or a run.
