TY - JOUR
T1 - Effect of Film Thickness on the High Frequency Magnetic Properties of Polycrystalline Fe-Ga Films
AU - Endo, Yasushi
AU - Sakai, Takumi
AU - Miyazaki, Takamichi
AU - Shimada, Yutaka
N1 - Funding Information:
ACKNOWLEDGMENT The authors thank Prof. Osamu Kitakami, Associate Prof. Satoshi Okamoto, and Assistant Prof. Nobuaki Kikuchi at Tohoku University for performing the photo lithography, and and Mr. Kunio Yanagi, Mr. Sigeyuki Sato, and Mr. Ryoichi Utsumi of Toei Scientific Industrial Corporation for measuring magnetostriction. This work was supported in part by JSPS KAKENHI Grant Number JP26289082, JP17H03226 and JP17F17070. This work was supported in part by CIES collaborative research from CIES, Tohoku University. This work was also supported in part by the Murata Science Foundation and Advanced Storage Research Consortium (ASRC) in Japan.
Publisher Copyright:
© 2017 IEEE.
PY - 2017/11
Y1 - 2017/11
N2 - This paper describes the effect of film thickness on the high frequency magnetic properties of polycrystalline Fe-Ga films. The damping constant (α) increases markedly from approximately 0.015 to 0.081 for a film thickness below 20 nm, reaches a maximum value of 0.084 at a thickness of 30 nm, and then decreases to 0.068 as the thickness further increases to 100 nm. All the values are much larger than those of a single crystal Fe-Ga film, indicating that the extrinsic damping overlaps with the intrinsic damping. The inhomogeneous broadening in a zero field [ΔH (0)] significantly increases with the film thickness due to the magnetic inhomogeneities, such as anisotropy dispersion and other effects. In addition, α increases markedly as the saturation magnetostriction (λs) increases. This behavior is very similar to those of Ni-Fe and Ni-Fe-M films. Therefore, these results demonstrate that α is correlated with λs regardless of the film thickness, and also sensitive to magnetic inhomogeneities.
AB - This paper describes the effect of film thickness on the high frequency magnetic properties of polycrystalline Fe-Ga films. The damping constant (α) increases markedly from approximately 0.015 to 0.081 for a film thickness below 20 nm, reaches a maximum value of 0.084 at a thickness of 30 nm, and then decreases to 0.068 as the thickness further increases to 100 nm. All the values are much larger than those of a single crystal Fe-Ga film, indicating that the extrinsic damping overlaps with the intrinsic damping. The inhomogeneous broadening in a zero field [ΔH (0)] significantly increases with the film thickness due to the magnetic inhomogeneities, such as anisotropy dispersion and other effects. In addition, α increases markedly as the saturation magnetostriction (λs) increases. This behavior is very similar to those of Ni-Fe and Ni-Fe-M films. Therefore, these results demonstrate that α is correlated with λs regardless of the film thickness, and also sensitive to magnetic inhomogeneities.
KW - Coplanar waveguide ferromagnetic resonance (CPW-FMR) measurement
KW - Fe-Ga film
KW - damping constant
KW - saturation magnetostriction
UR - http://www.scopus.com/inward/record.url?scp=85032976970&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85032976970&partnerID=8YFLogxK
U2 - 10.1109/TMAG.2017.2703119
DO - 10.1109/TMAG.2017.2703119
M3 - Article
AN - SCOPUS:85032976970
VL - 53
JO - IEEE Transactions on Magnetics
JF - IEEE Transactions on Magnetics
SN - 0018-9464
IS - 11
M1 - 7924417
ER -