A closed form of the spin-wave Green function is obtained for a system consisting of two different Heisenberg ferromagnets coupled by an interface. The calculations employ a tridiagonal matrix method and the random-phase approximation. The results are used to calculate the localized modes associated with an isolated impurity at or near the interface. Numerical examples of the modes are given, and they are found to exhibit various effects due to the interplay between the bulk and interface modes and the strength of the impurity-related interactions.
ASJC Scopus subject areas
- Condensed Matter Physics