Double-hump soliton excitations in an Antiferromagnetic spin lattice

Abstract

Using a modified Hamiltonian that takes into account both the bilinear and
D- M interactions as well as the biquadratic anisotropic interaction, the dynamical
theory of soliton excitation in a one-dimensional antiferromagnetic spin lattice is
investigated. The two coupled nonlinear partial differential equations that govern
the dynamics of the system are derived by introducing the Holstein -Primakoff
transformation, the coherent state ansatz, and the time-dependent variational
principle. The double- hump soliton propagation, the effect of interaction, and
finally the inhomogenity parameters are examined by the Sine-Cosine function
method.