Effect of exhaustion on the competition Kondo-magnetism in Kondo clusters

A numerical exact calculation is performed on a hexagonal cluster of 6 atoms with 6 localized electrons and a varying number of conduction electrons within the Kondo-lattice Hamiltonian including both intra-site and inter-site exchange interaction terms. We show that the Kondo effect is strongly decreased by a decrease of the number of conduction electrons, in good agreement with previous mean-field calculations and with the idea of exhaustion.