Solitons in one-dimensional Heisenberg ferromagnetic chain with linear magnetic field

Two kinds of soliton excitations in 1D ferromagnetic chain with linear magnetic field are considered. The results, two soliton solutions derived from two different modified NLS equations, all show that linear term of magnetic field has no influence on the shape and effective mass of each soliton, but changes the motional mode from uniformly motion to uniformly variable motion. Moreover, the energy of soliton appears the localized distribution after introducing the linear magnetic field. To introduce the linear magnetic can makes the excitation and motion of soliton more controllable without any bad damage in 1D ferromagnetic chain.