Asymptotic local moment formation in the Kondo lattice

A generalized Ginzburg-Landau theory is applied to the Kondo lattice model, taking account of all the modes of static thermal fluctuations of Kondo bosons in the mean mode-mode coupling approximation. The high-temperature asymptotic behaviors of thermodynamic quantities are determined. The result of magnetic susceptibility suggests that the local moments in the Kondo lattice are asymptotically free at high temperatures, similarly to the impurity Kondo system. We also discuss the possible smooth crossover to the low-temperature heavy-fermion state.