An integrable model of (2+1)-dimensional Heisenberg ferromagnetic spin chain and soliton excitations

We investigate the nonlinear spin dynamics of (2+1)-dimensional Heisenberg ferromagnetic (FM) spin chains with bilinear and anisotropic interactions in the semiclassical limit using the coherent state ansatz combined with the Holstein-Primakoff (HP) bosonic representation of spin operators. In the continuum limit the dynamics is found to be governed by a new integrable nonlinear Schrodinger type equation in (2+1) dimensions. The integrability of the equation is studied by constructing Lax pair of operators. The multisoliton solution is generated through the Darboux transformation. We also propose a model representing the (2+1)-dimensional inhomogeneous Heisenberg FM spin chain and the effect of inhomogeneity is understood by performing a perturbation analysis. Finally, the modulation instability aspects are discussed via analytic solutions and graphical illustrations.