Thermal Modulation of Magnetization Dynamics in Nanometer-Thick L10-FePt Nanogranular and Continuous Films for High-Density Magnetic Recording Media
Thermal Modulation of Magnetization Dynamics in Nanometer-Thick L10-FePt Nanogranular and Continuous Films for High-Density Magnetic Recording Media
复制标题
DOI：
10.1021/acsanm.3c00283
复制
发表时间：
2023-03
影响因子：
5.9
通讯作者：
Y. Sasaki;I. Suzuki;R. Mandal;S. Kasai;Yukiko K. Takahashi
中科院分区：
文献类型：
--
作者：
Y. Sasaki;I. Suzuki;R. Mandal;S. Kasai;Yukiko K. Takahashi
磁记录介质中的磁热调制是一种提高记录密度的新技术，L10-FePT是一种很有前途的磁记录介质材料，但由于其磁化动力学在太赫兹频率范围内，以吉尔伯特衰减常数α为特征的磁化动力学实验观测存在技术难度。太赫兹自旋电子学中的一项前沿技术--全光泵浦-探测方法，使我们能够通过加热来实现对纳米薄膜中太赫兹磁化动力学的检测。本文用全光学方法讨论了L10-FePT纳米颗粒薄膜和连续薄膜的磁化动力学的热调制。随着温度的升高，纳米颗粒薄膜的有效阻尼常数从0.18降低到0.064，热调制降低了非本征贡献，而使α增加到530K以上。这一关于磁阻尼热调制的研究对设计未来的高密度磁记录介质具有重要的意义。
Thermal modulation of magnetism in magnetic recording media is a novel technique to increase the recording density.L10-FePt is a promising material for the media; however, experimental observation of its magnetization dynamics characterized by the Gilbert damping constantαis technically difficult because the dynamics is in the terahertz (THz) frequency range. A cutting edge technique in THz spintronics, an all-optical pump–probe method, leads us to achieve the detection of THz magnetization dynamics in nanometer-scale thin films with thermal heating. Here, thermal modulation of the magnetization dynamics forL10-FePt nanogranular and continuous films is discussed using the all-optical method. The effective damping constant for the nanogranular film decreased from 0.18 to 0.064 with increasing the temperature, and the thermal modulation decreased the extrinsic contribution, while this increasedαabove 530 K. This observation regarding the thermal modulation of the magnetic damping is valuable to design future high-density magnetic recording media.