Origin of magnetism and dynamics (Part 2)

Racetrack Memory has the potential to replace existing memory devices by allowing high packing density and fast access times while being non-volatile due to saving the information in a magnetic layer.
Its architecture relies on the movement of the magnetic bits, represented by domain walls, by electrical currents. In order to understand the mechanism of domain wall motion, this part of the tutorial focuses on the dynamics of magnetic moments in a nanowire. Starting from the Landau–Lifshitz–Gilbert equation, the equations of motion of domain walls will derived using the Lagrange formalism in a one-dimensional model.
The mathematical results will be visualized by illustrating the torques acting on the magnetization created by the relevant energy terms and spin-transfer torques. Subsequently, the model is extended to antiferromagnetically coupled systems in which the exchange coupling torque plays a major role.
Finally, the threshold current density will be discussed which is a limiting factor for applications like Racetrack Memory.

In contrast to Part I, Part II will be a presentation with only a short discussion afterwards.