Green's function theory for a magnetic impurity layer in a ferromagnetic Ising film with transverse

[摘要] A Green's function formalism is used to calculate the spectrum of localized modes of an impurity layer implanted within a ferromagnetic thin film. The equations of motion for the Green's functions are determined in the framework of the Ising model in a transverse field. We show that depending on the thickness, exchange and effective field parameters, there is a crossover effect between the surface modes and impurity localized modes. For thicker films the results show that the degeneracy of the surface modes can be lifted by the presence of an impurity layer. (C) 2004 Elsevier B.V. All rights reserved.

[发布日期] 2004-12-01

[关键词] Heisenberg ferromagnet;Ising model-transverse;Green's function;spin wave;impurities modes