Role of domain-wall structure in weak-torque light-metal/ferrimagnet bilayers

Determine whether the internal domain-wall configuration, particularly the absence of chiral Néel-wall stabilization in light-metal/Gd25(Fe9Co1)75 bilayers, contributes to the suppression of current-driven domain-wall propagation.

Background

The experiments detect finite but extremely weak damping-like torques in Mn/GFC and Ti/GFC bilayers, yet do not observe reproducible directional domain-wall motion. The authors propose that weak interfacial Dzyaloshinskii–Moriya interaction may favor Bloch-type walls rather than the Néel-type walls that couple most efficiently to damping-like torques.

Although the measured field-assisted motion suggests that the torque itself is very small, the authors explicitly state that the additional influence of the domain-wall structure has not been resolved. Establishing this contribution would distinguish insufficient torque generation from inefficient coupling to the domain-wall configuration.

References

While our measurements of field-assisted DW motion in Figs. 3(c,d) suggest that the torque magnitude itself is extremely small, the additional role of DW structure cannot be excluded at this stage.

— Challenges in orbital current-driven domain wall motion in light metal/ferrimagnet heterostructures  (2609.04811 - Kang et al., 4 Sep 2026) in Section III, subsection “Absence of current-driven DW motion in Mn/GdFeCo and Ti/GdFeCo bilayers”