Anisotropic Ferromagnetic Chain Research Articles

Soliton Scattering on Impurities with Modified Exchange Interactions in Anisotropic Ferromagnetic Chains

The soliton propagation in an anisotropic ferromagnetic chain where the exchange interactions of an impurity spin with its neighbors are modified is investigated. We considered easy-axis anisotropy of the chain which leads to the formation of bright soliton solutions. The character of the soliton-impurity interaction is different when the exchange coupling of the spin is modified in the x,y-plane or in the z-direction. Our results show that the action of the defect depends on the soliton wave number in a complicated manner and for large velocities becomes significant. A comparison with the soliton dynamics in the presence of point defects is made.

The effect of the magnetic field on the stability and excitation spectrum of spin nanoclusters in anisotropic ferromagnetic chains

The spectral problem of the internal mode oscillations of a spin nanocluster in an anisotropic ferromagnetic chain placed a magnetic field has been solved exactly using the discrete Takeno-Homma model. A stability diagram on the plane of exchange and magnetic field parameters is constructed for spin clusters having arbitrary dimensions. Explicit expressions for the nanocluster internal mode oscillations are found, and their frequency dependences on the exchange and magnetic field parameters are calculated.