FMR spectrum-linewidth and spin diffusion length in Cu/Ni80Fe20/N(N=Cu,Cu/Pt)

Abstract

We have investigated the magnetic damping in two types of multilayer films, Cu(10 nm)/Ni 80 Fe 20 (3 nm)/Cu (d Cu) and Cu(10 nm)/Ni 80 Fe 20 (3 nm)/Cu(d Cu)/Pt(2 nm). Temperature dependence of the damping parameter and FMR linewidth with various Cu thickness d Cu were measured. Spin diffusion length increased with decreasing temperature. We also measured the temperature dependence of FMR linewidth for the Cu/ Ni 80 Fe 20 /Cu(d Cu)/Pt films with d Cu = 400 nm, 800 nm. The increase of FMR linewidth with decreasing temperature suggested that the damping increased by spin diffusion in Cu layer.

Nonlocal magnetization dynamics in ferromagnetic heterostructures

“…Solid lines are fits based on spin-pumping theory. Adapted from Yakata et al, 2005. The magnetization of the thin ferromagnetic layer precesses in the external magnetic field, while the other static magnetic layer acts as a spin sink. No modification of the damping coefficient was measured for GaAs͉Fe͉Au structures without a second Fe layer.…”

Temperature Dependences of Spin-Diffusion Lengths of Cu and Ru layers

“…It is known that the spin-diffusion length increases at a low temperature. 4) In this work, we focused on the Cu and Ru layers as the NM layers in a multilayer structure and measured their spin-diffusion lengths. The Cu and Ru layers are well known interlayers in a multilayer structure, particularly for a synthetic antiferromagnetic structure.…”

Nonlocal Magnetization Dynamics in Ferromagnetic Heterostructures

“…The temperature dependence of the Gilbert damping in such trilayers has been measured recently by the same group (Yakata et al, 2005), see Fig. 9.…”