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

通过对外延异质结构的原位研究，分离了体积和界面对磁化动力学的不同阻尼贡献。研究了Fe/GaAs（110）外延在不同主要晶体学方向上的自旋泵浦贡献。对于（110）薄膜，所有主要方向都位于一个薄膜平面内，因此很容易到达。研究1- 20nm范围内的无帽薄膜，以确定和分离不同的弛豫过程（吉尔伯特阻尼，非均匀阻尼，自旋泵浦）。这将通过使用完全相同的样品对有盖和无盖薄膜进行现场厚度相关测量来完成。在考虑所有阻尼贡献的情况下，首次将界面阻尼的不同贡献基片-膜和膜-盖层分离开来。自旋泵浦将与衬底参数相关，如掺杂和产生以及欧姆或肖特基接触。此外，还将通过波长、极化、螺旋度、强度和磁化与激光之间的角度来研究圆偏振光对红外光谱的影响。

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.