抄録
We study the magnetic ground state of a generalized Kondo lattice model with classical localized spins, which includes antiferromagnetic exchange interaction J between localized spins. We determine the magnetic phase diagram on the plane of J and fermion concentration n, examining all possibilities of planar order of the localized spins in two dimensions. We find canted ferromagnetic phases, diagonal spiral phases, stripe spiral phases as well as the Néel ordered phase and the ordinary ferromagnetic phase. The densities of states of the fermions for these localized spin state are calculated. For small n, we analytically examined the stability of the Néel state and the ferromagnetic state in detail in any dimensions. We also discuss the t-J limit, JK/t → ∞, for small n.