Partial Kondo Screening in Honeycomb Lattice

In this work, we study the Kondo lattice problem on honeycomb lattices using the large-N mean-field theory. Our numerical solutions to the self-consistent mean-field equations reveal that, depending on electron filling and Kondo interaction strength, the system can exhibit partial Kondo screening (PKS), where one sublattice shows finite Kondo coherence while the other exhibits magnetic (or charge) order without Kondo coherence. To explain this phenomenon, we construct a Ginzburg-Landau theory that identifies the general conditions favoring PKS, which can be applied to other bipartite lattices. Notably, the PKS phase breaks inversion symmetry, signifying a genuine second-order phase transition at the onset of the Kondo coherence. These results go beyond the conventional Doniach phase diagram and offer some insights into Kondo physics in bipartite lattice systems.