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Title: Role of crystalline and damping anisotropy to the angular dependences of spin rectification effect in single crystal CoFe film

The angular dependence of the microwave-driven spin rectification (SR) effect in single crystalline Co0.5Fe0.5alloy film is systematically investigated. Due to the strong current-orientation dependent anisotropic magnetoresistance (AMR), the SR effects in CoFe film strongly deviate from the ordinary sin 2φMcosφMrelation withφMdefined as the magnetization angle away from the current. A giant Gilbert damping anisotropy in the CoFe film with a maximum–minimum ratio of 520% is observed, which can impose a strong anisotropy onto magnetic susceptibility. The observed unusual angular dependence can be well explained by the theory including current-orientation dependent AMR and anisotropic magnetic susceptibility. Our work also suggests that the strong current-orientation dependent AMR in single crystalline CoFe film could exist up to the gigahertz frequency range.

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Award ID(s):
1941426 1933301
Publication Date:
Journal Name:
New Journal of Physics
Page Range or eLocation-ID:
Article No. 093047
IOP Publishing
Sponsoring Org:
National Science Foundation
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