Separation of the Spin Pumping From the Gilbert Damping by In Situ Investigations and Optically Modified Spin Pumping

• Applicant: Dr. Florian M. Römer
• Subject Area: Experimental Condensed Matter Physics
• Term: from 2016 to 2019
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 321725013

Different damping contributions of the volume and interface on the magnetization dynamics will be separated by in situ investigation of epitaxial hetero structures. The spin pumping contribution of epitaxial Fe/GaAs(110) shall be investigated for the different main crystallographic directions. For (110) films all main directions lay within one film plane and are therefore easy accessible. Uncapped thin films in the range of 1-20 nm will be investigated to determine and separate the different relaxation processes (Gilbert damping, inhomogeneous damping, spin pumping). This will be done by in situ thickness dependent measurements of capped and uncapped film using the exactly same sample. The different contributions of the interface damping substrate-film and film-capping will be separated for the first time under consideration of all damping contributions. The spin pumping will be correlated to the substrate parameters like doping and creating and ohmic or Schottky like contact.Additionally the influence of circular polarized IR light will be investigated by means of wavelength, polarization, helicity, intensity and angle between the magnetization and laser light.

• DFG Programme: Research Grants