Speaker: Bernhard Keimer - Max Planck Institute
Time: December 11, 2019 :: 10:30AM - 11:30AM
Quantum materials with 4d valence electrons serve as a platform for fundamental concepts such as unconventional superconductivity, Kitaev spin liquids, and solid-state analogues of the Higgs mode in particle physics. However, basic questions about the electronic structure of these materials remain unanswered, because key interaction parameters (including the Hund’s coupling, spin–orbit coupling, and exchange interactions) are comparable in magnitude and their interplay is poorly understood. We will discuss recent inelastic neutron and x-ray scattering experiments on spin waves, spin-orbit excitons, and spin-state transitions, which provide new insight into these interactions and their influence on the phase behavior of model materials including Ca2RuO4, Ca3Ru2O7, SrRu2O6, and RuCl3.