Co/Pt多層膜およびCoPt合金膜のダンピング定数評価

カテゴリ: 論文誌(論文単位)

グループ名: 【A】基礎・材料・共通部門

発行日: 2016/05/01

タイトル(英語): Evaluation of Damping Constants for Co/Pt Multilayers and CoPt Alloy Films

著者名: 草薙　勇作（東北大学多元物質科学研究所），岡本　聡（東北大学多元物質科学研究所），菊池　伸明（東北大学多元物質科学研究所），北上　修（東北大学多元物質科学研究所），加藤　剛志（名古屋大学エコトピア科学研究所），岩田　聡（名古屋大学エコトピア科学研究所）

著者名(英語): Yusaku Kusanagi (Institute of Multidisciplinary Research for Advanced Materials, Tohoku University), Satoshi Okamoto (Institute of Multidisciplinary Research for Advanced Materials, Tohoku University), Nobuaki Kikuchi (Institute of Multidisciplinary Research for Advanced Materials, Tohoku University), Osamu Kitakami (Institute of Multidisciplinary Research for Advanced Materials, Tohoku University), Takeshi Kato (EcoTopia Science Institute, Nagoya University), Satoshi Iwata (EcoTopia Science Institute, Nagoya University)

キーワード: ダンピング定数，強磁性共鳴，垂直磁化膜，Co/Pt多層膜，CoPt合金膜　　damping constant，ferromagnetic resonance，perpendicular magnetic film，Co/Pt multilayer film，CoPt alloy film

要約(英語): In this study, the damping constants of Co/Pt multilayers and hexagonal-closed-packed (hcp) CoPt alloy films are investigated by using a vector network analyzer ferromagnetic resonance spectroscopy (VNA-FMR) and time resolved magneto-optical Kerr effect (TR-MOKE). For Co/Pt multilayer films, very clear linear relationship between FMR frequency and absorption peak width is found. From this relationship, the damping constants of Co/Pt multilayers are evaluated to be about 0.02～0.07 with very small extrinsic contributions. On the other hand, for CoPt alloy films, the absorption peak width becomes wider and exhibits very little FMR frequency dependence. The damping constants of CoPt alloy films evaluated by TR-MOKE, however, are as small as about 0.03～0.06, being almost the same with that Co/Pt multilayers. These discrepancies found in CoPt alloy films can be explained by assuming the large distribution of magnetic anisotropy. Thus the damping constant of CoPt alloy films are some what larger than that of Co/Pt multilayers when these results are compared at same Pt composition.

本誌: 電気学会論文誌A（基礎・材料・共通部門誌） Vol.136 No.5 （2016） 特集：電磁界を用いた自然災害軽減のための観測・予測・解析技術

本誌掲載ページ: 317-323 p

原稿種別: 論文／日本語

電子版へのリンク: https://www.jstage.jst.go.jp/article/ieejfms/136/5/136_317/_article/-char/ja/