| Author(s): |
Sangita S. Kalarickal; Pavol Krivosik; Mingzhong Wu; C E. Patton; Michael Schneider; Pavel Kabos; Thomas J. Silva; John P. Nibarger; |
| Title: |
Ferromagnetic resonance linewidth in metallic thin films: Comparison of measurement methods |
| Published: |
May 22, 2006 |
| Abstract: |
Strip line (SL), vector network analyzer (VNA), and pulsed inductive microwave magnetometer (PIMM) techniques were used to measure the ferromagnetic resonance (FMR) linewidth for a series of Permalloy films with thicknesses of 50 and 100 nm. The SL-FMR measurements were made for fixed frequencies from 1.5 to 5.5 GHz. The VNA-FMR and PIMM measurements were made for fixed in-plane fields from 1.6 to 8 kA/m (20-100 Oe). The results provide a confirmation, lacking until now, that the linewidths measured by these three methods are consistent and compatible. In the field format, the linewidths are a linear function of frequency, with a slope that corresponds to a nominal Landau-Lifshitz phenomenological damping parameter α value of 0.007 and zero frequency intercepts in the 160-320 A/m (2-4 Oe) range. In the frequency format, the corresponding linewidth versus frequency response shows a weak upward curvature at the lowest measurement frequencies and a leveling off at high frequencies. |
| Citation: |
Journal of Applied Physics |
| Volume: |
99 |
| Issue: |
093909 |
| Pages: |
pp. 1 - 7 |
| Keywords: |
damping;FMR;magnetodynamics;PIMM |
| Research Areas: |
Electromagnetics |
| PDF version: |
 Click here to retrieve PDF version of paper (405KB) |
