Damping by Slow Relaxing Rare Earth Impurities inNi80Fe20

Abstract

Doping Ni80Fe20 by heavy rare earth atoms alters the magnetic relaxation properties of this material drastically. We show that this effect can be well explained by the slow relaxing impurity mechanism. This process is a consequence of the anisotropy of the on site exchange interaction between the 4f magnetic moments and the conduction band. As expected from this model the magnitude of the damping effect scales with the anisotropy of the exchange interaction and increases by an order of magnitude at low temperatures. In addition, our measurements allow us to determine the relaxation time of the 4f electrons as a function of temperature.

Attenuation of propagating spin wave induced by layered nanostructures

“…Another possible reason of the enhanced damping is that the Pt would act as a dopant into the FeNi films. It is consistent with previous studies 22,23 where heavy-metal dopants in FeNi can increase the damping.…”

Ab InitioCalculation of the Gilbert Damping Parameter via the Linear Response Formalism

“…This allows us to study with moderate effort the influence of varying the alloy composition on the damping parameter α. Corresponding work has been done in particular using permalloy as a starting material and adding transition metals (TM) [16] or rare earth metals [17]. Fig.…”

Local control of magnetic damping in ferromagnetic/non-magnetic bilayers by interfacial intermixing induced by focused ion-beam irradiation

“…The damping coefficient can be modified by introducing doping elements including rare earths [4][5][6][7] or transition metal 8,9 elements, with the dopant introduced by co-deposition, usually co-sputtering. A disadvantage of this approach is that the entire material is doped.…”