[9p-PB1-1~80] 10 スピントロニクス・マグネティクス（ポスター講演）

[9p-PB1-4] スパッタによるa-面配向のMn₃Sn薄膜

〇呉 承俊¹、森田 正¹、池田 智紀²、大兼 幹彦²、角田 匡清²、安藤 康夫² (1.アルバック未来研、2.東北大)

キーワード：反強磁性、異常ホール効果、スパッタ

Many of theoretical studies have indicated that a large anomalous Hall effect (AHE) could be also observed in antiferromagnet (AFM). As the first case in AFM, Mn₃Sn has been experimentally found to exhibit a large AHE [1]. The origin of AHE is not magnetization but significantly enhanced berry curvature which is from specific band structure in k-space. The enhanced berry curvature can play a similar role of magnetic field resulting Hall effects. For practical application, establishment of thin film deposition technique is necessary. Recently, it was reported that randomly oriented polycrystalline Mn₃Sn films showed a large AHE at room temperature [2]. Given that the direction of Berry curvature is parallel to (0001) c-plane of hexagonal Mn₃Sn crystal, (11-20) a- or (1-100) m-oriented films are desirable to apply for Hall bar measurement.
In this study, highly a-oriented Mn₃Sn thin films were grown on m-plane sapphire substrates with low-temperature grown Mn₃Sn buffer layers by sputtering deposition technique, and their crystallinity and magnetic properties were investigated by X-ray diffraction and SQUID magnetometer, respectively. Fig.1 shows XRD pattern of highly a-oriented Mn₃Sn film. The crystallographic orientations of Mn₃Sn domains are found to be sensitively influenced by substrate temperature, thickness and composition ratio of Mn_3+αSn buffer layer.
This work was supported in part by Center for Spintronics Research Network, Tohoku University (CSRN).