Co25Fe75 Thin Films with Ultralow Total Damping of Ferromagnetic Resonance
Abstract
We measure the dynamic properties of Co25Fe75 thin films grown by dc magnetron sputtering. Using ferromagnetic resonance spectroscopy, we demonstrate an ultralow total damping parameter of <0.0013 in the out-of-plane configuration, whereas for the in-plane configuration, the minimum total damping is <0.0020. In both cases, low inhomogeneous linewidth broadening occurs in macroscopic films. The minimum full-width at half-maximum linewidth is 1 mT at a 10-GHz resonance frequency for a 12-nm thick film. We characterize the morphology and structure of these films as a function of seed layer combinations, which indicate a large variation in the qualitative behavior of the in-plane linewidth vs resonance frequency. Finally, we use wavevector-dependent Brillouin light scattering spectroscopy to characterize the spin-wave dispersion at wave vectors up to 23 μ m-1.
- Publication:
-
Physical Review Applied
- Pub Date:
- May 2019
- DOI:
- 10.1103/PhysRevApplied.11.054036
- Bibcode:
- 2019PhRvP..11e4036E