Spin currents and domain wall dynamics based on the spin Seebeck effect

• Applicants: Professor Dr. Mathias Kläui; Professor Dr. Ulrich Nowak
• Subject Area: Experimental Condensed Matter Physics ; Theoretical Condensed Matter Physics
• Term: from 2011 to 2021
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 198571487

The recently found spin Seebeck effect refers to a spin current and spin accumulation induced by a temperature gradient in a ferromagnetic material. This effect opens new perspectives for spin caloritronic applications, combining the spin degrees of freedom with caloric properties. In a joint theoretical and experimental effort the applicants will investigate spin currents in ferromagnets, induced by thermal gradients. We will use spin model simulations as well as a state-of-the-art micromagnetic framework, which includes thermodynamic aspects, and compare the simulation results with their experimental counterpart. Localized laser (pulse) heating applied to magnetic nano- and microstructures will be used to tailor the temperature gradients. To detect a spin accumulation, we will use the inverse spin Hall effect and engineer the structures to determine its sign, position and origin. In a next step we will investigate the inuence of the thermal spin currents on confined domain walls by simulating and measuring the depinning and propagation properties of the walls. Objectives include a deeper understanding of the origin and the nature of the thermally induced spin currents and a determination of the torques that these spin currents exert on the domain walls.

• DFG Programme: Priority Programmes
• Subproject of: SPP 1538: Spin Caloric Transport (SpinCaT)