Third Funding Period 2024-2027:

A01  Spin+Orbit Coupling: Orbitronics and spin-orbit effects

Prof. Dr. Mathias Kläui (Institute of Physics, JGU)

Project A01 explores the field of orbitronics including novel current-induced orbital torques for efficient spin switching. These torques are based on the generation of orbital angular momentum by the orbital Hall and orbital Rashba Edelstein effects that can be orders of magnitude more efficient than the equivalent effects for spin. We will study these mechanisms and the conversion of orbital angular momentum to spin that eventually leads to the generation of torques. Beyond spin and orbital torques, self torques are generated in these systems with symmetry breaking. We identify the torque origin and determine the mechanism leading to these torques. Finally, we study the effects of all these torques on selected antiferromagnetic systems to optimize the current-induced switching of devices with such magnetic order.

Second Funding Period 2020-2023:

A01  Spin+Orbit-Coupling: Insulator Spin-Orbitronics – Spin-orbit torques and chiral exchange interactions

Prof. Dr. Mathias Kläui (Institute of Physics, JGU)

In Project A01, we are investigating spin-orbitronics in the material class of magnetic insulators with enhanced properties such as low damping. We combine ferro-, ferri- and in particular antiferromagnetic insulators with heavy metal layers that in combination yield novel exchange coupling phenomena and interfacial spin – orbit torques. We will probe intralayer and interlayer chiral exchange interactions and resulting chiral spin structures in magnetic insulator heterostructures. The dynamics will be excited using spin-orbit torques that switch the order parameters in magnetic and in particular antiferromagnetic insulators. Ultimately, efficient interfacial spin-orbit effects will be probed in 2D magnetic systems.

First Funding Period 2016-2019:

A01  Spin+Orbit-Coupling: Understanding the origin of spin-orbit torques

Prof. Dr. Mathias Kläui (Institute of Physics, JGU)

The overall aim of project A01 is to understand the impact of spin-orbit coupling on the static magnetization configurations and the dynamics of the spin switching. We will use Kerr microscopy to study the magnetization reversal and correlate the underlying effects with spin-spin and spin-orbit coupling resulting from judiciously chosen materials. To achieve this general aim, magnetic domain imaging will be performed using a new magneto-optical Kerr microscopy setup. The experimentally measured spin structures and spin dynamics will be compared with the spatially resolved magnetization patterns and dynamics from corresponding micromagnetic simulations. This comparison will allow us to identify the acting torques and to quantify their symmetries and strengths. To achieve this, the project has three aims:

Aim 1: Development of the necessary tools and methods to measure and characterize spin-orbit effects

Aim 2: Understanding of the origin and amplitude of symmetry allowed spin-orbit induced coupling

Aim 3: Characterization of domain wall motion in systems with strong spin-orbit coupling