A03 Spin+Orbitronics: Electrically generated spin-orbit torques and pure-spin currents
Prof. Dr. Jairo Sinova (Institute of Physics, JGU Mainz)
In project A03, spin-orbit coupling effects leading to spin-orbit torques will be studied theoretically. We will calculate the spin currents generated in a paramagnetic material by the spin Hall effect as well as the non-equilibrium spin density in the free carriers in a ferromagnetic metal, which in turn exerts a torque on the local magnetic moments via the spin-spin exchange interaction. By mapping ab-initio band structure calculations in different thin film hetero-structures to microscopic tight-binding and effective models and using this as input for non-equilibrium spin-charge transport codes, a full microscopic analysis will be carried out to predict the torques. From the experimental results, we will deduce the strengths of the spin currents and resulting spin-orbit torques that will help in understanding their origin. The results will then be used to optimize the systems for maximum spin manipulation efficiency.
Aim 1: Develop a microscopic understanding of SOTs and related spin-orbit interaction induced phenomena by performing ab-initio calculations in a variety of hetero-structures and material compositions, as well as the dependence of magnetocrystalline anisotropy on the strain and interface, and chiral interactions;
Aim 2: Derive effective models in order to gain a deep physical understanding of the SOTs and related spin-orbit-induced effects in terms of generic interactions and projections from the ab initio calculations.