Abstract The dynamic magnetization of magnetic materials is of fundamental interest and is essential for various applications in magnetic storage, spin wave and wireless communication areas. Traditionally, rare-earth-doped ferromagnets show an enhancement of the Gilbert damping parameter due to the slow relaxation of the 4f-electron spins of rare-earth atoms. The exchange coupling between a ferromagnetic garnet thin film and a nanometer rare-earth thin film has been rarely explored. In this work, we fabricated and systematically studied microstructural, static and dynamic magnetic properties of yttrium iron garnet (YIG)/dysprosium (Dy) heterojunctions. Large modulations of the out-of-plane magnetic anisotropy field, Gilbert damping parameter and magneto-optic Kerr rotation angle have been realized in single-crystalline YIG thin films capped by rare-earth Dy nano-films. Both the effective Gilbert damping parameter, αeff , and the Kerr rotation angle, increase by 300% for the YIG/Dy(60 nm) heterostruture compared to the bare YIG ferromagnet. The enhanced αeff strongly depends on the out-of-plane magnetic anisotropy field, which arises from the interfacial exchange coupling between YIG and Dy nano-films. Our findings provide a robust route to control both magnetization dynamics and magneto-optic properties using rare-earth nano-films.

中文翻译：

---

稀土镝纳米薄膜包覆的单晶钇铁石榴石磁化动力学和磁光特性的控制

摘要 磁性材料的动态磁化具有重要意义，对于磁存储、自旋波和无线通信领域的各种应用至关重要。传统上，由于稀土原子的 4f 电子自旋的缓慢弛豫，稀土掺杂的铁磁体表现出吉尔伯特阻尼参数的增强。铁磁石榴石薄膜和纳米稀土薄膜之间的交换耦合很少被探索。在这项工作中，我们制造并系统地研究了钇铁石榴石 (YIG)/镝 (Dy) 异质结的微观结构、静态和动态磁性能。面外磁各向异性场的大调制，吉尔伯特阻尼参数和磁光克尔旋转角已在稀土 Dy 纳米薄膜覆盖的单晶 YIG 薄膜中实现。与裸 YIG 铁磁体相比，YIG/Dy(60 nm) 异质结构的有效吉尔伯特阻尼参数 αeff 和克尔旋转角增加了 300%。增强的 αeff 强烈依赖于面外磁各向异性场，这是由 YIG 和 Dy 纳米膜之间的界面交换耦合引起的。我们的发现提供了一种使用稀土纳米薄膜控制磁化动力学和磁光特性的可靠途径。增强的 αeff 强烈依赖于面外磁各向异性场，这是由 YIG 和 Dy 纳米膜之间的界面交换耦合引起的。我们的发现提供了一种使用稀土纳米薄膜控制磁化动力学和磁光特性的可靠途径。增强的 αeff 强烈依赖于面外磁各向异性场，这是由 YIG 和 Dy 纳米膜之间的界面交换耦合引起的。我们的发现提供了一种使用稀土纳米薄膜控制磁化动力学和磁光特性的可靠途径。