Towards pure spin currents in epitaxial all oxide heterostructures

• Applicant: Dr. Matthias Althammer
• Subject Area: Experimental Condensed Matter Physics
• Term: from 2018 to 2023
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 406078190

Over the last years, the generation and detection of pure spin currents, i.e. the flow of angular momentum without any accompanying charge current, has been successfully realized. This opened fascinating opportunities for fundamental physics experiments and novel applications in spin electronics. However, a profound understanding of the phenomena associated with pure spin currents and the materials systems suitable for their study is still missing. The main objective of this research proposal is the systematic study of pure spin current physics in all oxide heterostructures, which are promising for this purpose but hardly investigated so far. On the one hand, the planned experiments are expected to provide a profound understanding of the rich variety of phenomena associated with spin-orbit interaction in oxide materials and its dependence on the specific material parameters. On the other hand, the project aims to develop and investigate novel materials with large spin Hall angle, i.e. with a large efficiency for electrical generation and detection of pure spin currents. Moreover, it aims at the tunability of spin-orbit coupling in oxides via strain, oxygen vacancies, and temperature. The boost of the efficiency for spin current generation and detection is a prerequisite for the application of pure spin currents in efficient spintronic devices. The ambitious project objectives will be met by fabricating high-quality oxide heterostructures by laser-molecular beam epitaxy and by systematically studying pure spin current generation and detection in experiments based on longitudinal spin Seebeck effect and spin Hall magnetoresistance. The applicants contribute broad expertise in both thin film technology and the experimental characterization techniques for spin current phenomena to the successful implementation of the ambitious research program.

• DFG Programme: Research Grants
• Co-Investigator: Professor Dr. Rudolf Gross