Suppression of Standing Spin Waves in Low-dimensional Ferromagnets

Abstract: We examine the experimental absence of standing spin wave modes in thin magnetic films, by means of atomistic spin dynamics simulations [1]. Using Co on Cu(001) as a model system, we demonstrate that by increasing the number of layers, the optical branches predicted from adiabatic first-principles calculations are strongly suppressed, in agreement with spin-polarized electron energy loss spectroscopy measurements reported in the literature. Our results suggest that a dynamical analysis of the Heisenberg model is sufficient in order to capture the strong damping of the standing modes.

[1] Phys. Rev. Lett. 107, 037202 (2011).