Mass of a skyrmion under a driving current

We present arguments for a mass term in the Landau-Lifshitz-Gilbert equation based on the notion of mass as an inertial quantity. From trajectories of skyrmions in a confining potential and a 1-D potential we see evidence for a mass-inertia connection. We derive an expression for the effective mass for skyrmions, 1.6ε×10−23kg, where ε accounts for the mismatch between the local magnetic moment induced on the conduction electrons and its corresponding effect on the current-driven skyrmion and varies from 10−2 to 1.