Novel interpretation of recent experiments on the dynamics of domain walls along ferrimagnetic strips

Open Access

Abstract

[EN] Domain wall motion along ferrimagnets is evaluated using micromagnetic simulations and a collective-coordinates model, both considering two sublattices with independent parameters. Analytical expressions are derived for strips on top of either a heavy metal or a substrate with negligible interfacial Dzyaloshinskii-Moriya Interaction. The work focuses its ndings in this latter case, with a eld-driven domain wall motion depicting precessional dynamics which become rigid at the angular momentum compensation temperature, and a current-driven dynamics presenting more complex behavior, depending on the polarization factors for each sublattice. Importantly, our analyses provide also novel interpretation of recent evidence on current-driven domain wall motion, where walls move either along or against the current depending on temperature. Besides, our approach is able to substantiate the large non-adiabatic efective parameters found for these systems. ; Project No. MAT2017-87072-C4-1-P from the (Ministerio de Economía y Competitividad) Spanish Government Project No. SA299P18 from the (Consejería de Educación of) Junta de Castilla y León.