Abstract
The ability to tailor the damping factor is essential for spintronic and spin-torque applications. Here, we report an approach to manipulate the damping factor of FeGa/MgO(001) films by oblique deposition. Owing to the defects at the surface or interface in thin films, two-magnon scattering (TMS) acts as a non-Gilbert damping mechanism in magnetization relaxation. In this work, the contribution of TMS was characterized by in-plane angular dependent ferromagnetic resonance. It is demonstrated that the intrinsic Gilbert damping is isotropic and invariant, while the extrinsic mechanism related to TMS is anisotropic and can be tuned by oblique deposition. Furthermore, the two and fourfold TMS related to the uniaxial magnetic anisotropy and magnetocrystalline anisotropy were discussed. Our results open an avenue to manipulate magnetization relaxation in spintronic devices.
Highlights
In the past decades, controlling magnetization dynamics in magnetic nanostructures has been extensively studied due to its great importance for spintronic and spin-torque applications [1,2]
The magnetic relaxation is described within the framework of the Landau-Lifshitz Gilbert (LLG) phenomenology using the Gilbert damping factor α [3]
In addition to the intrinsic damping, the two-magnon scattering (TMS) process serves as an important extrinsic mechanism in magnetization relaxation in ultrathin films due to the defects at surface or interface [8,9]
Summary
In the past decades, controlling magnetization dynamics in magnetic nanostructures has been extensively studied due to its great importance for spintronic and spin-torque applications [1,2]. In addition to the intrinsic damping, the two-magnon scattering (TMS) process serves as an important extrinsic mechanism in magnetization relaxation in ultrathin films due to the defects at surface or interface [8,9]. This process describes the scattering between the uniform magnons and degenerate final-state spin wave modes [10]. For the geometry of off-normal deposition, it has been demonstrated to provoke shadow effects and create a periodic stripe defect matrix This can introduce a strong uniaxial magnetization anisotropy (UMA) perpendicular to the projection of the atom flux [16,17,18,19]. The strong connection between the extrinsic TMS and the magnetic anisotropy, as well their direct impact on the damping constants, are systemically investigated, which offer us a useful approach to tailor the damping factor
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
