We investigated effects of inserted ultrathin Pt buffer on the perpendicular magnetic properties of Ta/TbFeCo/Ta layered structures. For Tb-rich TbFeCo films buffered with Ta and Ta/Pt a compensation thickness is observed at ∼ 6 nm, where the net saturation magnetization vanishes. The perpendicular magnetic anisotropy properties of two structures are found to be governed by a competition of a perpendicular bulk anisotropy and an in-plane interface anisotropy. Compared with Ta-buffered TbFeCo films, the counterparts with insertion of Pt buffer exhibits a larger negative interface anisotropy. A large variation of saturation magnetization and perpendicular magnetic anisotropy with increasing inserted thickness of Pt buffer is observed in the Ta/Pt/TbFeCo/Ta structure. This can be ascribed to the interface-driven variation of exchange interaction between Tb and FeCo at the interface, confirmed by thermomagnetic measurements. A clear correlation between the interface-driven variation of exchange interaction and perpendicular magnetic properties of the TbFeCo films is identified. Our results show the interface plays an important role in the perpendicular magnetic properties of TbFeCo films, which is critical for the application in spintronic devices.

中文翻译：

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插入超薄 Pt 缓冲层对 Ta/TbFeCo/Ta 层状结构垂直磁性能的影响


我们研究了插入的超薄 Pt 缓冲层对 Ta/TbFeCo/Ta 层状结构垂直磁性能的影响。对于用 Ta 和 Ta/Pt 缓冲的富 Tb TbFeCo 薄膜，在 ~ 6 nm 处观察到补偿厚度，其中净饱和磁化强度消失。发现两种结构的垂直磁各向异性性质是由垂直体各向异性和面内界面各向异性的竞争决定的。与Ta缓冲TbFeCo薄膜相比，插入Pt缓冲的对应薄膜表现出更大的负界面各向异性。在 Ta/Pt/TbFeCo/Ta 结构中观察到饱和磁化强度和垂直磁各向异性随着 Pt 缓冲层插入厚度的增加而发生很大变化。这可以归因于界面处 Tb 和 FeCo 之间交换相互作用的界面驱动变化，这一点已通过热磁测量得到证实。界面驱动的交换相互作用变化与 TbFeCo 薄膜的垂直磁性之间存在明显的相关性。我们的结果表明，界面在 TbFeCo 薄膜的垂直磁性能中起着重要作用，这对于自旋电子器件的应用至关重要。