Kondo Physics Across Single-Impurity and Lattice Limits in Moiré Material
ORAL · Invited
Abstract
Moiré materials provide a uniquely tunable platform for exploring Kondo physics across the regimes of single impurities and periodic Kondo lattices. In this talk, I will present two complementary approaches to controlling many-body Kondo screening in moiré systems. First, in engineered Kondo lattices realized in moiré Mott insulators such as WSe₂/WS₂ in proximity to WSe₂ conduction layer, we uncover a gate-tunable evolution from a heavy Fermi liquid to a Kondo insulator. Using slave-boson mean-field theory benchmarked by one-dimensional DMRG, we map the magnetic-field and temperature phase diagram and find good agreement with experimental observations. Second, in the single Kondo impurity limit realized by vacancy-induced quantum spins hybridized with flat moiré bands in twisted bilayer graphene, atomistic modeling combined with numerical renormalization group analysis reveals twist-angle–dependent Kondo physics. We identify van Hove–enhanced Kondo screening and a broad, magic-angle–sensitive distribution of Kondo temperatures. These results demonstrate that moiré platforms offer a versatile setting for tuning Kondo interactions and realizing emergent correlated ground states across impurity and lattice limits.
*The work at the UT Knoxville was primarily supported by the National Science Foundation Materials Research Science and Engineering Center program through the UT Knoxville Center for Advanced Materials and Manufacturing (DMR-2309083). The work at LANL was carried out under the auspices of the U.S. DOE NNSA under contract No. 89233218CNA000001 through the LDRD Program, and was supported by the Center for Nonlinear Studies at LANL, and was performed, in part, at the Center for Integrated Nanotechnologies, an Office of Science User Facility operated for the U.S. DOE Office of Science, under user proposals #2018BU0010 and #2018BU0083.
