Observations of thermally excited ferromagnetic resonance on spin torque oscillators having a perpendicularly magnetized free layer
- Spintronics Research Center, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Ibaraki 305-8568 (Japan)
Measurements of thermally excited ferromagnetic resonance were performed on spin torque oscillators having a perpendicularly magnetized free layer and in-plane magnetized reference layer (abbreviated as PMF-STO in the following) for the purpose of obtaining magnetic properties in the PMF-STO structure. The measured spectra clearly showed a large main peak and multiple smaller peaks on the high frequency side. A Lorentzian fit on the main peak yielded Gilbert damping factor of 0.0041. The observed peaks moved in proportion to the out-of-plane bias field. From the slope of the main peak frequency as a function of the bias field, Lande g factor was estimated to be about 2.13. The mode intervals showed a clear dependence on the diameter of the PMF-STOs, i.e., intervals are larger for a smaller diameter. These results suggest that the observed peaks should correspond to eigenmodes of lateral spin wave resonance in the perpendicularly magnetized free layer.
- OSTI ID:
- 22273723
- Journal Information:
- Journal of Applied Physics, Vol. 115, Issue 17; Conference: 55. annual conference on magnetism and magnetic materials, Atlanta, GA (United States), 14-18 Nov 2010; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); ISSN 0021-8979
- Country of Publication:
- United States
- Language:
- English
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