抄録
Free oscillations, switching and ferromagnetic resonance of Permalloy thin films are measured changing, for each film, various parameters including temperature. It is shown that the damping factor λ in the free oscillations of Permalloy thin film is composed of three parts as
λ=λin+λedd+kHy,
where λin is due to the intrinsic damping plus the damping from the anisotropy dispersion, λedd due to the eddy current damping, which is represeted as 1.0×1017d2 (cps) as a function of the thickness d, and kHy due to the high power effect probably caused by the increased excitation of the spin wave modes. In the last term Hy is the amplitude of the applied pulse field and k is a constant which depends on the film thickness. The value of λin is about 1.05×108 (cps) and is in good agreement with the minimum value of λ ever obtained for Permalloy films by various measurements.
