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.
