Synthetic route to low damping in ferromagnetic thin-films
S. Azzawi,
A. Umerski,
L. C. Sampaio,
S. A. Bunyaev,
G. N. Kakazei,
D. Atkinson
Affiliations
S. Azzawi
Department of Physics, Durham University, Durham DH1 3LE, United Kingdom
A. Umerski
School of Mathematics and Statistics, The Open University, Milton Keynes MK7 6A, United Kingdom
L. C. Sampaio
Centro Brasileiro de Pesquisas Físicas (CBPF), Rio de Janeiro, Brazil
S. A. Bunyaev
Institute of Physics for Advanced Materials, Nanotechnology and Photonics (IFIMUP), Departamento de Física e Astronomia, Universidade do Porto, Porto 4169-007, Portugal
G. N. Kakazei
Institute of Physics for Advanced Materials, Nanotechnology and Photonics (IFIMUP), Departamento de Física e Astronomia, Universidade do Porto, Porto 4169-007, Portugal
D. Atkinson
Department of Physics, Durham University, Durham DH1 3LE, United Kingdom
Previous theory indicated that the individual monolayers within transition metal ferromagnet thin-films contribute different magnitudes to the total ferromagnetic damping. Here, the aim was to investigate if the thin-film damping could be reduced by electronic engineering of the higher damping regions via localized doping. We present new theoretical analysis and experimental results for sputtered Co thin-films in which the upper and lower surface regions were locally doped with Cr. Theory indicates that local doping does reduce the damping and the experiments show a comparable reduction of the damping with increasing local doping up to 30% Cr, while the measured damping falls further with higher local doping, which may be attributed to changes in the film structure. This work opens a route to create low-damping magnetic thin-films.
