The domain wall dynamics driven by an out-of-plane magnetic field was measured for a series of magnetic trilayers with different strengths of the interfacial Dzyaloshinskii-Moriya interaction (DMI). The features of the field-driven domain wall velocity curves strongly depend on the ratio of the field $H_D$ stabilizing chiral Néel walls to the demagnetizing field within the domain wall, $H_{\mathrm{DW}}$. The measured Walker velocity, which in systems with large DMI is maintained after the Walker field, giving rise to a velocity plateau up to the Slonczewski field $H_S$, can be related to the DMI strength. Yet, when $H_D$ and $H_{\mathrm{DW}}$ have comparable values, a careful analysis needs to be done in order to evaluate the impact of the DMI on the domain wall velocity. By means of a one-dimensional model and two-dimensional simulations, we extend this method and we clarify the interpretation of the experimental curves measured for samples where $H_D$ and $H_{\mathrm{DW}}$ are comparable.

• Received 11 December 2020
• Revised 17 June 2021
• Accepted 21 June 2021

DOI:https://doi.org/10.1103/PhysRevB.104.014405