Role of crystalline and damping anisotropy to the angular dependences of spin rectification effect in single crystal CoFe film
Fanlong Zeng, Xi Shen, Yi Li, Zhe Yuan, Wei Zhang, Yizheng Wu
Abstract
Abstract The angular dependence of the microwave-driven spin rectification (SR) effect in single crystalline Co 0.5 Fe 0.5 alloy 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 2 φ M cos φ M relation with φ M defined 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.