Condensed Matter Theory Seminar | January 30, 14:00
Kondo screening in the multiorbital Hubbard models and the two-channel spin-orbital Kondo model
In this talk, we highlight the role of Kondo screening in strongly correlated many-body physics. First, we investigate the Mott transition in multiorbital Hubbard models with Hund’s coupling, using dynamical mean-field theory (DMFT) with the numerical renormalization group (NRG) impurity solver. We show that the quasiparticle weight vanishes continuously or exhibits a discontinuous jump at zero temperature, depending on the degeneracy of the local ground state. We interpret this behavior in terms of Kondo screening of the effective impurity. We also identify the unstable DMFT branch as a Fermi liquid and connect it to quantum-critical scaling. Second, we revisit the two-channel spin-orbital Kondo (2soK) model and its anisotropic extensions. Combining NRG with analytical arguments, we uncover previously overlooked non-Fermi-liquid fixed points in the 2soK model.
Seoul National University
0.03
Contact: Fabian Kugler