Gopman Daniel B, Sampath Vimal, Ahmad Hasnain, Bandyopadhyay Supriyo, Atulasimha Jayasimha
Materials Science & Engineering Division, National Institute of Standards and Technology, Gaithersburg, MD, 20899 USA.
Mechanical and Nuclear Engineering, Virginia Commonwealth University, Richmond, VA, 23284 USA.
IEEE Trans Magn. 2017 Nov;53(11). doi: 10.1109/TMAG.2017.2700404. Epub 2017 May 3.
We present measurements of the static and dynamic properties of polycrystalline iron-gallium films, ranging from 20 nm to 80 nm and sputtered from an FeGa 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 -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 = (18 ± 4) pJ/m and Gilbert damping = 0.042 ± 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.
我们展示了从20纳米到80纳米、由FeGa靶溅射而成的多晶铁镓薄膜的静态和动态特性测量结果。使用宽带铁磁共振装置在宽频率范围内，当外部静态磁场在平面内施加时，观察到了垂直驻立自旋波共振。在每个频率下对应最强共振峰的磁场用于确定有效磁化强度、品质因数和吉尔伯特阻尼。此外，在几个频率下观察到了自旋波模式对场位置的依赖性。对宽带动态特性的分析确定了40纳米和80纳米厚薄膜的交换刚度 = (18 ± 4) pJ/m以及吉尔伯特阻尼 = 0.042 ± 0.005。这些值与外延生长薄膜中的值大致一致，表明了用于微波应用的磁致伸缩FeGa薄膜的工业制造潜力。
