Static and dynamic magnetic properties of sputtered Fe-Ga thin films

Published: May 03, 2017


Daniel B. Gopman, Vimal Sampath, Hasnain Ahmad, Supriyo Bandyopadhyay, Jayasimha Atulasimha


We present measurements of the static and dynamic properties of iron-gallium films, ranging from 20~nm to 80~nm and sputtered from an $\mathrm{Fe_{0.8}Ga_{0.2}}$ target. Using a broadband ferromagnetic resonance setup in a wide frequency range, perpendicular standing spin-wave resonances were observed with the external static magnetic field applied in--plane. The field corresponding to the strongest resonance peak at each frequency is used to determine the effective magnetization, the $g$--factor and the Gilbert damping. Furthermore, the dependence of spin- wave mode on field-position is observed for several frequencies. The analysis of broadband dynamic properties allows determination of the exchange stiffness $A = \left ( 18 \pm 4 \right ) \mathrm{pJ/m}$ and Gilbert damping $\alpha = 0.042 \pm 0.005$ for 40~nm and 80~nm thick films. These values are approximately consistent with values seen in epitaxially grown films, indicating the potential for industrial fabrication of magnetostrictive FeGa films for microwave applications.
Citation: IEEE Transactions on Magnetics
Pub Type: Journals
Created May 03, 2017, Updated November 10, 2018