Speaker
Description
Magnetic bubbles are skyrmionic spin structures stabilized by dipolar interactions. Recent theoretical investigations predict a GHz gyrotropic motion of these topological configurations after excitation in a restoring potential, analogous to vortex gyration. However, in contrast to vortices, bubbles are predicted to exhibit inertial effects. Here we demonstrate the presence of an inertial mass in a magnetic bubble by imaging its gyrotropic trajectory using pump-probe x-ray holography. We find that the inertial mass is very large compared to other magnetic systems, which we attribute to the non-local energy reservoir of the bubble's breathing mode. The breathing mode is a unique feature of the geometrically confined skyrmionic spin structure, which is a direct consequence of its topology, and thus lends itself to describe the inertia of Skyrmions in terms of a topological mass.
