There is a notable increase in magnetization damping in thin Permalloy (Ni81Fe19, "Py" ) films as thier thickness is reduced, inversely proportional to thier thickness. This indicates an effective magnetization relaxation mechanism at the film surface. The damping effect depends on
the morphology of the surface and the type of protective layer used, and is much larger in structures of Pt/Py/Pt than in Cu/Py/Cu,Nb/Py/Nb or SiO2/Py/PR, where PR is photoresist. There is a strong correlation betwen the magnetization damping and the electrical resistivity as a function of film
thickness in the SiO2/Py/PR samples. These findings suggest that electron scattering at the surface, modulated by the spin- orbit interaction is the cause of the increased magnatization damping.
By: S.Ingvarsson+ L. Ritchie X. Y. Liu, Gang Xiao (Brown University Physics Dept. Providence, RI) J. C. Slonczewski, P, T. Trouilloud, R. H. Koch
Published in: RC21967 in 2001
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