Fig. 1
From: Stochastic dynamics and pattern formation of geometrically confined skyrmions
Field dependence of the total topological charge. Red region: external fields below the strip-out instability leading to spin spiral segments; dark green: transition regime; bright green: ensemble of skyrmions; blue: completely field-polarized island, where skyrmions collapse under the strong external field. Solid red line indicates the magnetic field B = 1.5 T used for subsequent calculations. For each step in the vertically applied field 20 randomly magnetized configurations of a 21 nm diameter nanodisk were relaxed towards the nearest metastable state on the energy hypersurface at T = 0 K
