GOALI: High Magnetic Anisotropy Materials for Ultrahigh Density Heat-assisted Magnetic Recording Media.

目标：用于超高密度热辅助磁记录介质的高磁各向异性材料。

• 批准号: 1611424
• 负责人: Kai Liu
• 金额: $ 40万
• 依托单位: University of California-Davis
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-07-01 至 2019-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1611424&HistoricalAwards=false
• 关键词: GOALI; Magnetic; Anisotropy; Materials; Ultrahigh

Over the last six decades, the areal density of magnetic recording has increased by eight orders of magnitude. These rapid advancements have fundamentally changed information technology and the way of life. The information is stored in tiny magnets, like compasses with nanometer sizes. As each bit of information is stored over an ever-smaller volume, it is essential to use materials that are still stable at extremely small dimensions against thermal effects. This material property is known as the magnetic anisotropy, which anchors magnetic moments in place, enabling their practical use. This project aims at realizing materials with high magnetic anisotropy using convenient and benign synthesis conditions, combined with control over the material properties, towards applications in next generation ultrahigh density magnetic recording media and rare-earth-free and precious-metal-free permanent magnets. This GOALI partnership between U.C. Davis and Seagate offers an exciting opportunity to rapidly transfer research results into technology. This would potentially speed up the adaptation of the emerging heat-assisted magnetic recording technology. Advances in more powerful permanent magnets would impact numerous industry sectors, including hybrid and electric vehicles, magnetically levitated trains, wind turbines, power storage, magnetic refrigeration, etc. The partnership also provides opportunities to train junior researchers in industry research and development laboratories, in addition to excellent exposure to research experience in university and national laboratory and user facilities. The team plans to initiate and actively participate in a variety of efforts to broaden participation from underrepresented groups through internships, graduate course offering, exchange visits with Seagate, and other specific programs at the Magnetism Conference.High magnetic anisotropy materials have critical applications in next generation ultrahigh density heat-assisted magnetic recording media as well as high energy density permanent magnets. Alloys of ordered FePt in the L10 phase is an ideal candidate for recording media applications. However, a critical challenge has been the high annealing temperature necessary to transform the as-deposited low anisotropy phase into the desirable high anisotropy one. This project will achieve high magnetic anisotropy L10 FePt-based thin films using atomic-scale multilayer sputtering and rapid thermal annealing. Magnetic properties of these materials will be tailored to achieve the desirable high anisotropy, large saturation magnetization, and low Curie temperature using ternary FePt-based alloys through proper tuning of the effective valence electron number. These approaches will be extended to realize L10 FeNi films that are alternative type of permanent magnets using earth abundant elements. A true understanding of the disorder-order phase transformation in these thin films will be gained, and quantitative evaluation of the phase fractions will be obtained. The partnership between U.C. Davis and Seagate will help to achieve L10 FePt and FeNi based alloys that can be readily synthesized, with controlled anisotropy at the atomic scale and minimized switching field distribution. Such materials have potentially transformative technological impacts, in speeding up the adaption for the emerging ultrahigh density heat-assisted magnetic recording technology and in the realization of high energy density permanent magnets that are rare-earth-free and precious-metal-free.

在过去的六十年里，磁记录的面密度增加了八个数量级。这些快速进步从根本上改变了信息技术和生活方式。这些信息存储在微小的磁铁中，例如纳米尺寸的指南针。由于每一位信息存储在越来越小的体积中，因此必须使用在极小尺寸下仍能稳定地抵抗热效应的材料。这种材料特性被称为磁各向异性，它将磁矩固定在适当的位置，从而使其能够实际使用。该项目旨在利用方便和良性的合成条件，结合对材料性能的控制，实现具有高磁各向异性的材料，以应用于下一代超高密度磁记录介质以及无稀土和无贵金属的永磁体。 U.C. 之间的 GOALI 合作伙伴关系Davis 和 Seagate 提供了一个将研究成果快速转化为技术的令人兴奋的机会。这可能会加速新兴热辅助磁记录技术的应用。更强大的永磁体的进步将影响众多行业领域，包括混合动力和电动汽车、磁悬浮列车、风力涡轮机、电力存储、磁制冷等。该合作伙伴关系还提供了培训行业研发实验室的初级研究人员的机会，除了在大学和国家实验室和用户设施中获得良好的研究经验之外。该团队计划发起并积极参与各种努力，通过实习、研究生课程提供、与希捷的交流访问以及磁学会议上的其他具体项目，扩大代表性不足群体的参与。高磁各向异性材料在下一代领域具有关键应用超高密度热辅助磁记录介质以及高能量密度永磁体。 L10 相有序 FePt 合金是记录介质应用的理想选择。然而，一个关键的挑战是将沉积态的低各向异性相转变为所需的高各向异性相所需的高退火温度。该项目将利用原子级多层溅射和快速热退火来实现高磁各向异性的 L10 FePt 基薄膜。这些材料的磁性将通过适当调整有效价电子数来定制，以使用三元 FePt 基合金实现所需的高各向异性、大饱和磁化强度和低居里温度。这些方法将扩展到实现 L10 FeNi 薄膜，这是使用地球丰富元素的替代类型永磁体。将获得对这些薄膜中无序相变的真正理解，并对相分数进行定量评估。 U.C. 之间的合作关系Davis 和 Seagate 将帮助实现易于合成的 L10 FePt 和 FeNi 基合金，在原子尺度上具有受控的各向异性和最小化的开关场分布。此类材料具有潜在的变革性技术影响，可加快新兴超高密度热辅助磁记录技术的应用，并实现不含稀土和贵金属的高能量密度永磁体。

项目成果

Improved Power Factor and Mechanical Properties of Composites of Yb 14 MgSb 11 with Iron

Yb 14 MgSb 11 与铁复合材料改善功率因数和机械性能

• DOI: 10.1021/acsaem.9b02168
• 发表时间: 2020
• 期刊: ACS Applied Energy Materials
• 影响因子: 6.4
• 作者: Perez, Christopher J.;Qi, Xiao;Chen, Zhijie;Bux, Sabah K.;Chanakain, Sevan;Li, Billy;Liu, Kai;Dhall, Rohan;Bustillo, Karen C.;Kauzlarich, Susan M.
• 通讯作者: Kauzlarich, Susan M.

First-order reversal curve of the magnetostructural phase transition in FeTe

• DOI: 10.1103/physrevb.95.214402
• 发表时间: 2017-06-05
• 期刊: PHYSICAL REVIEW B
• 影响因子: 3.7
• 作者: Frampton, M. K.;Crocker, J.;Zieve, R. J.
• 通讯作者: Zieve, R. J.

Electrically Enhanced Exchange Bias via Solid-State Magneto-ionics

• DOI: 10.1021/acsami.1c11126
• 发表时间: 2021-08-04
• 期刊: ACS APPLIED MATERIALS & INTERFACES
• 影响因子: 9.5
• 作者: Murray, Peyton D.;Jensen, Christopher J.;Liu, Kai
• 通讯作者: Liu, Kai

Two-way magnetic resonance tuning and enhanced subtraction imaging for non-invasive and quantitative biological imaging

• DOI: 10.1038/s41565-020-0678-5
• 发表时间: 2020-05-25
• 期刊: NATURE NANOTECHNOLOGY
• 影响因子: 38.3
• 作者: Wang, Zhongling;Xue, Xiangdong;Li, Yuanpei
• 通讯作者: Li, Yuanpei