TY - JOUR
T1 - Influence of Pt doping on Gilbert damping in permalloy films and comparison with the perpendicularly magnetized alloy films
AU - Mizukami, Shigemi
AU - Kubota, Takahide
AU - Zhang, Xianmin
AU - Naganuma, Hiroshi
AU - Oogane, Mikihiko
AU - Ando, Yasuo
AU - Miyazaki, Terunobu
PY - 2011/10/1
Y1 - 2011/10/1
N2 - Effects of Pt doping on magnetic properties and Gilbert damping are investigated for Ni80Fe20 permalloy films to compare with damping in alloy films containing Pt with a large perpendicular anisotropy. Gilbert damping constant α and g-factor g for (Ni80Fe 20)100-xPtx (x = 0(34at. %) are evaluated from out-of-plane angular variations of ferromagnetic resonance (FMR) linewidth and resonance field with an analysis based on the Landau-Lifshitz-Gilbert equation. Data of angular dependence of the FMR linewidth are fitted reasonably well by a theoretical model without having to take into account any extrinsic influences on linewidth, thereby allowing us to determine precise values of α. The α values show variation with increasing Pt concentration rising by ∼0:06 at a Pt concentration of 34at.%, which is very close to those in perpendicularly magnetized CoCrPt and FePt film reported recently. Nevertheless, Gilbert damping rate G for the Pt doped permalloy films is smaller than those in CoCrPt and FePt films. These experimental results are discussed with a spin-orbit torque theory.
AB - Effects of Pt doping on magnetic properties and Gilbert damping are investigated for Ni80Fe20 permalloy films to compare with damping in alloy films containing Pt with a large perpendicular anisotropy. Gilbert damping constant α and g-factor g for (Ni80Fe 20)100-xPtx (x = 0(34at. %) are evaluated from out-of-plane angular variations of ferromagnetic resonance (FMR) linewidth and resonance field with an analysis based on the Landau-Lifshitz-Gilbert equation. Data of angular dependence of the FMR linewidth are fitted reasonably well by a theoretical model without having to take into account any extrinsic influences on linewidth, thereby allowing us to determine precise values of α. The α values show variation with increasing Pt concentration rising by ∼0:06 at a Pt concentration of 34at.%, which is very close to those in perpendicularly magnetized CoCrPt and FePt film reported recently. Nevertheless, Gilbert damping rate G for the Pt doped permalloy films is smaller than those in CoCrPt and FePt films. These experimental results are discussed with a spin-orbit torque theory.
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U2 - 10.1143/JJAP.50.103003
DO - 10.1143/JJAP.50.103003
M3 - Article
AN - SCOPUS:80054895729
VL - 50
JO - Japanese Journal of Applied Physics, Part 1: Regular Papers & Short Notes
JF - Japanese Journal of Applied Physics, Part 1: Regular Papers & Short Notes
SN - 0021-4922
IS - 10 PART 1
ER -