Three-Dimensional Visualization of the Fast Magnetization Dynamics and Burst-Like Emission of Spin Waves in a Permalloy Film (Micromagnetic Simulation)

The paper proposes a combined method for visualizing the motion of magnetization in a three-dimensional fragment of a permalloy film containing a moving domain wall. Images of a dynamically transforming surface are created, which is the preimage of the curve belonging to a two-dimensional sphere | m( r,t ) | = 1 . Preimage curves of the individual points lying on this sphere are depicted as well. Tonal images are constructed that reflect changes in the rotational speeds of the magnetization vector m at different points, as well as images of markers indicating the positions of the Bloch points. By image stacking, it becomes possible to simultaneously monitor the structural transformations of the magnetization (including topological rearrangements) and see the fast rotations of the magnetization vector (in particular, due to spin-wave processes). Various scenarios of dynamic behavior are implemented by creating a surface relief with variable geometry at the film boundary.