Quantum criticality in an artificial moire Kondo lattice

We artificially construct a two-dimensional Kondo lattice by combining transition metal dichalcogenide (TMD) moire superlattices with an angle-misaligned monolayer. At half band filling of the moire lattice, strong on-site Coulomb repulsion localizes electrons to form a triangular lattice, which provides local spin moments for the Kondo lattice. Angle-misaligned TMD monolayer hosts itinerate electrons coupled with the local moment layer via spin-exchange interaction. We demonstrate typical Kondo characteristics in this artificial system, including heavy fermion behaviors and a sudden change in the size of the Fermi surface during the Kondo breakdown. By tuning the density of local moments, we observe a quantum phase transition between heavy fermions and orbital-selective Mott states. Our study provides a highly tunable Kondo lattice system for discovery of rich exotic states in the Kondo phase diagrams and a better understanding of Kondo-related physics.