Exploring Kondo Physics in Kagome Lattices

Metallic kagome systems have been a subject of considerable interest in recent years, as they provide a reliable framework for studying interesting phenomena associated with their distinctive band structure. The coexistence of bands with Dirac points similar to those found in graphene, in addition to a completely flat-band makes this an ideal structure to investigate topological and correlation effects, protected by lattice symmetries. One of the fundamental correlation phenomena is the Kondo screening effect, with features that depend critically on the density of states (DOS) near the Fermi level. As symmetries can be affected by applied strain in materials, which in turn modifies electronic states, we believe that understanding the interplay between strain and the Kondo effect in kagome lattices may reveal insights on correlated systems. To achieve this, we employ the Single Impurity Anderson Model (SIAM) and the numerical renormalization group (NRG) to analyze the Kondo effect in kagome nanoribbons under applied uniaxial strain. It was shown that this approach allows for a thorough characterization of the occurrence and suppression of Kondo screening in a controlled manner. Furthermore, we have found that strain manipulation enables precise control over the realization or suppression of the Kondo effect in the impurity-plus-ribbon system. In addition to this, we obtain insights into the spatial extent of the Kondo cloud. Based on these results, we conclude that strain is a powerful tuning parameter in kagome nanoribbons, which underlies the possibility of tailoring electronic properties in correlated systems. It is therefore reasonable to assume that the ability to modulate the Kondo effect via strain could lead to novel applications in quantum materials that rely on strongly interacting electrons.