Kondo screening in high-spin side-coupled two-impurity clusters

We study the system of two magnetic impurities described by a two-impurity Kondo model where only the first impurity couples directly to the conduction band, while the second impurity interacts with the first through Heisenberg exchange coupling in a 'side-coupled' configuration. We consider various choices of the impurity spins (S1S2) and we contrast the regimes where the inter-impurity exchange coupling J is either lower or higher than the Kondo temperature TK(0) of the first impurity in the absence of the second. This model is a high-spin generalization of the two-impurity model for side-coupled double quantum dots which corresponds to the simplest S1 = S2 = 1/2 case, where the moments are Kondo-screened successively in two stages for JS2, there is no second stage of screening for JTK(0) the Kondo screening of the effective spin S1-S2 is found.