Various ordered states in Heisenberg FCC antiferromagnets with dipole-dipole interactions

Heisenberg antiferromagnet on a face-centered cubic (fcc) lattice with a nearest-neighbor exchange interaction is known to order antiferromagnetically with type-I spin structure. On the other hand, Heisenberg magnet on a fcc lattice with only magnetic dipole-dipole interactions orders ferromagnetically. Both the antiferromagnetic nearest-neighbor exchange interaction and the dipole-dipole interactions introduce frustration into the Heisenberg magnets but differently. Here the Heisenberg fcc antiferromagnets, in which both interactions are included are investigated by numerically solving the Landau-Lifshitz (LL) equation. Various ordered states which include multi-K structures are obtained depending on the relative strength of the two kinds of interactions. (author)