Localized excitations and scattering of spin waves in ferromagnetic chains containing magnetic clusters
O.V. Charkina and M.M. Bogdan
B. Verkin Institute for Low Temperature Physics and Engineering of the National Academy of Sciences of Ukraine 47 Nauky Ave., Kharkiv 61103, Ukraine
Received March 2, 2018
The spectrum of localized excitations in an aniso-tropic one-dimensional ferromagnet containing a spin cluster of arbitrary size is found exactly within the framework of the discrete Takeno–Homma model. The boundaries of stability of spin nanoclusters are determined in dependence of their size and the exchange and the anisotropy parameter of the ferromagnet. The problem of the spin wave scattering against nanoclusters is solved and explicit analytical expressions for their reflection and transmission coefficients are obtained. A model of a metamaterial consisting of weakly interacting magnetic molecular nanoclusters and possessing re-vealed dynamic properties is proposed.
PACS: 75.10.Pq Spin chain models;
Key words: quasi-one-dimensional ferromagnet, spin cluster, Takeno–Homma equation, localized excitations, spin wave scattering.
Published online: May 28, 2018