Abstract
A Green's function method is used to obtain the spectrum of excitations
of two neighboring impurities in a semi-infinite ferromagnet. The
equations of motion for Green's functions are determined in the
framework of the Heisenberg model. The energies of non-resonant
localized modes are calculated as a function of the interaction
parameters for the exchange coupling between impurity-spin pairs,
host-spin pairs, and impurity-host neighbors, as well as the effective
field parameter at the impurity sites. With two impurities the system is
less symmetric and has more localized modes when compared with a single
impurity case. (C) 2011 Elsevier B.V. All rights reserved.
Users
Please
log in to take part in the discussion (add own reviews or comments).