Materials World Network: Ultrafast All-Optical Switching in Ferri-/Ferromagnetic Nanomagnets

技术简介:在美国国家科学基金会材料研究部（DMR）和德国Forschungsgemeinschaft的资助下，Holger Schmidt的应用光学小组（美国加州大学圣克鲁兹分校）和Manfred Albrecht的磁性纳米结构小组（德国开姆尼茨工业大学）将共同研究铁磁和铁磁纳米磁铁的全光磁化开关技术、材料和应用。具体的项目目标包括(i)使用铁磁材料在单畴纳米磁体中演示全光磁化开关；（ii）利用磁各向异性、居里温度和晶体学可调的磁性材料制备交换耦合异质结构；（iii）单个纳米磁体在铁磁和铁磁材料的各种组合中的超快切换演示；（四）研究了全光开关过程作为三维纳米磁体的函数，以及密集阵列中的磁环境。这项研究是通过Albrecht小组的材料专业知识和Schmidt小组开发的单纳米磁铁检测能力的结合而实现的。非技术概述：纳米磁铁已经被考虑用于下一代数据存储介质和其他自旋电子学应用一段时间了。最近，亚铁磁性材料中磁取向的超快全光开关的发现引起了人们的极大兴趣，因为它有可能创造出具有前所未有响应时间的数据存储介质。这种光交换层与交换耦合铁磁存储层的潜在组合非常吸引人，并提出了许多令人兴奋的材料问题。该项目将系统地探索这些材料在纳米级存储介质中的新组合。此外，该项目将通过创造独特和有益的教育经验，为不同层次的学生提供比在单一国家环境中可能提供的更广泛和更完整的教育。参与小组之间的互访时间相当长（每年2-4周），这将为合作者提供有意义的技术培训，以扩大学生的知识、沟通技巧和专业竞争力。除了一名研究生和一名博士后外，还将通过UC LEADS或UC CAMP项目招募来自代表性不足群体的本科生，并有机会与国外研究人员合作完成他们的高级论文。

TECHNICAL SUMMARY: With financial support provided by the Division of Materials Research (DMR) at the National Science Foundation and the Deutsche Forschungsgemeinschaft, this collaborative effort between the Applied Optics group of Holger Schmidt (UC Santa Cruz, USA) and the Magnetic Nanostructures group of Manfred Albrecht (Chemnitz University of Technology, Germany) will investigate techniques, materials, and applications of all-optical magnetization switching in ferro- and and ferrimagnetic nanomagnets. Specific project goals include (i) demonstration of all-optical magnetization switching in single-domain nanomagnets using ferrimagnetic materials; (ii) fabrication of exchange-coupled heterostructures using magnetic materials with adjustable magnetic anisotropy, Curie temperature, and crystallography; (iii) demonstration of ultrafast switching of single nanomagnets in various combinations of ferro- and ferromagnetic materials; and (iv) investigation of the all-optical switching process as a function of the three-dimensional nanomagnet, and the magnetic environment in a dense array. This research is enabled through the combination of the materials expertise of the Albrecht group and the single nanomagnet detection capabilities developed in the Schmidt group.NON-TECHNICAL SUMMARY: Nanomagnets have been under consideration for next generation data storage media and other spintronics applications for some time. Recently, the discovery of ultrafast all-optical switching of magnetic orientation in ferrimagnetic materials has received a lot of interest due to the potential to create data storage media with unprecedented response times. The potential combination of such an optical switching layer with an exchange-coupled ferromagnetic storage layer is highly intriguing and raises a number of exciting material questions. This project will systematically explore novel combinations of such materials in the context of nanoscale storage media. In addition, the project will provide students at different levels with a broader and more complete education than what would be possible in a uni-national setting by creating a unique and rewarding educational experience. Mutual visits between the participating groups for a substantial amount of time (2-4 weeks per year) will allow for meaningful training in the technique used by their collaborators to broaden student knowledge, communication skills, and professional competitiveness. Aside from one graduate student and one postdoc, undergraduate students from underrepresented groups will be recruited through the UC LEADS or UC CAMP program, and will be given the opportunity to complete their senior theses in collaboration with researchers from abroad.