Solitons in the two-dimensional antiferromagnetic Heisenberg model

An effective Hamiltonian of the two-dimensional antiferromagnetic Heisenber g model is derived by using the Holstein-Primakoff transformation. Three no nlinear coupled partial equations of motion are obtained. In the long-wavel ength approximation, these equations are reduced to the envelope function e quations by the method of multiple scales. The amplitude functions satisfy the nonlinear Schrodinger equation. Introducing an inverse scattering trans formation, the single-, two- and multi-soliton solutions in the two-dimensi onal antiferromagnetic Heisenberg model are investigated.