Effect of magnetic domain-wall curvature on velocity in the creep regime

We study the effect of magnetic domain wall curvature on its dynamics in the creep regime in systems displaying Dzyaloshinskii-Moriya interaction (DMI). We first derive an extended creep model that is able to account for the finite curvature effect in magnetic bubble domain expansion. We then discuss the relative importance of this effect and discuss its dependence on the main magnetic and disorder parameters. We show this effect can be easily measured in <a:math xmlns:a="http://www.w3.org/1998/Math/MathML" display="inline"><a:mi>Pt</a:mi></a:math>/<c:math xmlns:c="http://www.w3.org/1998/Math/MathML" display="inline"><c:mi>Co</c:mi></c:math> multilayer samples, reporting a strong velocity reduction below a sample-dependent threshold value of the magnetic bubble radius. We finally show, both theoretically and experimentally, how the radius of magnetic bubbles can have a strong impact on the reproducibility of DMI measurements.