Fig. 2.

Evolution of the stable orbit $s_{\infty }$ with $J_{\text{dc}}$ for a negative (blue stars) or positive (orange stars) initial chirality. The second critical current $J_{\text{c2},C^{+}}$ is indicated by a dashed gray line. For an initial positive chirality, the vortex core reaches the magnetic dot limit for $|J_{\text{dc}}|\ge |J_{\text{c2},C^{+}}|$ with $J_{\text{c2},C^{+}}\simeq$$-$2.5 MA/cm², its chirality is then reversed to $C=-$1 and the vortex core polarity is either unchanged, leading to a steady-state regime similar to the one of a vortex with an initial negative chirality, or reversed, resulting in a resonant regime. The black dashed lines are the prediction of $s_{\infty }(J_{\text{dc}})$ from Eq. (2).